Chicken Terms/Definitions/Phrases


– A –

A rotten or otherwise inedible egg. Or an egg in which the embryo died during early incubation.

Age of lay
The age at which a pullet starts laying eggs. For instance, age of lay for lightweight breeds is generally 18 to 22 weeks; heavier begin laying around 24 to 26 weeks of age.

Air cell
The air space that develops at the rounded end of an egg, inside the shell between the inner and outer membranes.

Egg white.

A colorless gas that develops in a coop where the litter retains too much moisture. A high level of ammonia increases the flock’s susceptibility to respiratory disease.

A deworming preparation.

As hatched
Chicks that remain unsorted by gender at the time of hatch.

Sex-link characteristics within a pure breed, as compared to a sex-link hybrid.

– B –

A small chicken that’s about one-fourth to one-fifth as heavy as a large-size chicken and that generally weighs 2 pounds or less.

Beak trimming
Adjusting the length of mismatched halves of a chicken’s beak so the chicken can properly eat and preen.

A dense clump of small feathers attached under a chicken’s beak and always associated with a muff, a feature typical of Belgian Bearded D’Anvers, among other breeds.

Beetle brow
A prominent forehead projecting out over the eyes, a feature is typical of Brahmas, among others.

Billing out
The bad habit of a chicken or duck that wastes feed by using its beak or bill to scoop feed from a feeder onto the ground.

A collection of management precautions that keep a flock safe from disease.

Blood feather
Alternative name for a pinfeather, so called because pin feathers are filled with blood.

Blood spot
A harmless small, dark spot of blood that appears inside the shell of less than 1% of eggs laid.

The thin, moist protective coating on a freshly laid egg that prevents bacteria from entering the egg and minimizes evaporation of moisture from within the egg. Also called cuticle.

Break up
To discourage a hen from being broody so she will continue to lay eggs.

Breast blister
A blister resulting from excess pressure on a chicken’s breastbone, often occurring in heavy-breed males and in broilers.

Breed club
An organization that promotes a specific breed of poultry.

Usually some form of Cornish Cross that has the best feed conversion for its age and weight, and typically butchered at 4 to 7 weeks of age.

A artificial substitute for a mother hen, consisting of protective surroundings, feed, water, and a source of heat.

Brood patch
A bare area on a broody hen’s breast where she has removed the feathers so body warmth and moisture will be closer to the eggs.

The tendency for a hen to incubate a nestful of eggs until they hatch.

An abscess on the bottom of a chicken’s foot that may cause the chicken to limp and to sit on its hocks while resting.

– C –

Cage free
Not confined to a cage, but may be confined within housing.

To shine a bright light through an egg’s shell to examine the contents and determine its interior quality for eating or embryo development for hatching.

A device used for candling eggs.

A chicken’s unpleasant habit of eating another chicken’s flesh or feathers.

Chicken tractor
A portable or moveable chicken house or coop or pen that is easily movable to new ground, grass, or dirt on a regular basis. The process of regularly moving chicken tractor provides a clean area for chickens to eat grass/dirt/bugs/minerals while leaving their manure to fertilize the ground for future vegetation growth.

Chicken forum
An internet discussion site where people hold conversations in the form of posted messages about chickens.

Chicken blog
An internet journal, or web log, describing experiences, observations, and opinions of chicken topics and often having images and links to related websites.

Chicken wire
Wire mesh fencing made from thin wire twisted and woven together into a honeycomb pattern. Although chicken wire will confine chickens, it is not predator resistant because it tears easily.

A group of breeds for exhibition purposes. For example, The American Poultry Association groups large breeds according to their place of origin: American, Asiatic, Continental (European, not including England), English, and Mediterranean. A catchall class — All Other Standard Breeds (AOSB) — includes any that don’t fit into any another class.

Description of a chicken that has no feathers growing on the legs or feet.

The opening just inside a bird’s vent where the digestive, excretory, and reproductive tracts expel their respective products.

All the eggs a hen produces during one laying cycle. Also a group of eggs that hatch together.

An intestinal disease of chickens and other poultry, caused by coccidia, resulting in the interfere of nutrient absorption.

A male chicken that’s less than one year of age.

The state of health and cleanliness of a chicken or other type of poultry.

The body shape of a chicken, or other poultry, that is characteristic of its breed.

Coop training
Exposing a chicken, or other type of poultry, to conditions it will encounter during a poultry show. By minimizing stress, coop training increases the ability of the bird to achieve a higher placing at the show.

A pouch at the base of a chicken’s neck, on the left side, that bulges with feed after the bird has eaten.

Crop Impaction
A crop jammed with feed to the point that none can pass through to be digested.

Crossed Beak
A beak with the upper and lower halves growing in opposite directions. Also called scissor beak.

A form of feed consisting of pellets that have been crushed into smaller pieces.

Coarse, irregular barring such as occurs in the plumage of a Dominique.

To remove a chicken from a flock because of undesirable appearance or behavior.

The thin, moist protective coating on a freshly laid egg that prevents bacteria from entering the egg and minimizes evaporation of moisture from within the egg. Also called bloom.

– D –

A characteristic that makes a chicken less than perfect, compared to the standard description for the breed or variety.

To destroy an entire flock, typically to prevent the spread of a serious disease.

To treat a chicken with a medication to control internal parasitic worms.

Diatomaceous Earth
An abrasive powder, created by grinding up diatom fossils, used as an insecticide.

A characteristic that renders a chicken ineligible for receiving a show award.

Double Yolker
An egg containing two yolks.

Droopy Wing
A loosely carried wing, characteristic of some breeds including Japanese and Serama.

Dual Purpose Breed
A breed that is used for both meat and eggs. These breeds usually do not lay as well as those bred for laying and do not grow as well as those for meat production, but are a good compromise as farmstead chickens.

Dust Bath
A container of soft soil, loose sand, or deep bedding that chickens toss over themselves to condition their feathers and rid themselves of external parasites.

– E –

Ear Tuft
A clump of feathers sprouting from a tiny finger-like appendage protruding from the side of the neck just below the ear, as is characteristic of Araucanas.

Egg Basket
A container for collecting and transporting eggs.

Egg Bound
A condition where an egg gets stuck just inside the vent, often because the egg is too large or the hen is too fat or otherwise unhealthy.

Egg Carton
A rectangular box used for selling or storing eggs.

Egg Eating
A form of cannibalism in which chickens eat their own eggs (or those of other chickens).

Egg Tooth
A small, sharp cap at the tip of a newly hatched chick’s upper beak, used to help the chick break out of the egg before falling off after the hatch.

Egg Tray
A tray made of plastic or paper pulp, usually designed to hold 30 eggs. Also called a flat.

Egg Turner
A mechanical device that automatically rotates eggs during incubation.

A powdered mixture of natural salts and other minerals that help regulate body processes and maintain hydration.

Inflammation of a chicken’s small intestine resulting in diarrhea.

– F –

Feather Out
The process in which a baby chick grows its first full set of plumage.

Feather Picking
A form of cannibalism most common when chicks are starting to feather out and pick each other’s newly emerging feathers.

Fertile Eggs
Eggs from hens that have been exposed to a rooster and are therefore capable of producing chicks if incubated under appropriate conditions.

Description of chickens that are excitable.

Floor Eggs
Eggs laid on the coop floor, not in provided nests.

Any object — such as a cage, feed sack, or shoe soles — that may carry and transmit infectious organisms from one flock to another.

Forced molt
A process of restricting the water and feed intake of chickens (usually in Sept) to force the timing of the natural process of molting. Generally this will stop the egg production and allow the chicken to molt off significant feathering. After 3-5 weeks of restricted water and feed, then put chickens back on full feed and water to rebuild feathering. We have good luck using a chick grower feed for this rebuilding of feather process (4-6 weeks) and then change over to egg crumbles. Molting allows time for rest of egg production and allows nutrients to be used for new feathers.

Fowl Pox
A viral disease, spread by blood-sucking insects or through injuries, that causes scabby skin, fever, and loss of appetite. It has nothing to do with chicken pox in humans.

Free Choice
Water, feed, or supplements available to chickens at all times, so they can eat or drinkn as much as they need.

Free Range
Managing a flock by allowing it to roam around a large outdoor area.

Frozen body tissues, typically the comb, wattles, and/or toes.

– G –

Genetic Diversity
Degree of variation at the gene level. The greater a flock’s diversity, the more robust it is and able to resist stresses, including disease.

A chicken’s mechanical stomach, where feed is ground up prior to digestion.

Grandma’s Chickens
Heritage chicken breeds, typically Rhode Island Red or Plymouth Rock, that may be either pure or crossed with other heritage breeds.

Grand Master Exhibitor
A designation by the American Poultry Association for a member who accumulates 100 points by winning a sufficient number of class championships in a single variety of a single breed.

Small, hard objects, such as pebbles or coarse sand, eaten by a chicken to help the gizzard break down tough foods for digestion.

– H –

A chicken’s neck plumage.

The ability of fertile eggs to hatch when incubated.

A business — such as Cackle Hatchery® — that hatches poultry eggs and sells the chicks, usually of several different breeds and species.

Hatching Eggs
Eggs that are intended for incubation, rather than for eating. The main difference is are that table eggs aren’t necessarily fertile, while hatching eggs must be fertile.

Heavy Breed
A chicken breed that’s more round than slender, and generally weighs at least 6 pounds (hens) or 8 pounds (roosters).

Hen Feathered
A chicken breed in which the sex feathers and color markings are the same for both the hen and rooster, a characteristic of Sebrights.

The ability of a characteristic to be genetically transmitted from a chicken to its offspring.

Heritage chickens
Sometimes referred to as traditional breeds or old-time breeds, heritage chickens have these characteristics: natural mating, good foragers, good broody hens and good mothers, disease resistance, good fertility, longevity, alert for good natural flight or fight responses, domesticated qualities for human care, and usually a good sustainable dual meat and egg producer.

The joint between a chicken’s thigh and shank, corresponding to the human ankle.

The offspring of a rooster and a hen of two different breeds, one or both of which might also be hybrid.

– I –

A blocked body passage, such as the crop (occurring when a chicken eats something it can’t digest) or the cloaca (a result of a stuck egg).

A mechanical device designed for hatching fertile eggs.

– J –

Jungle Fowl
Chickens originating in the jungles and forests of southern Asian that are the ancestors of all domestic chickens.

– K –

The bony ridge along the center of a chicken’s breast, which resembles a boat’s keel.

– L –

Description of plumage in which a narrow edge of contrasting color surrounds each feather.

Lash Egg
Coagulated bits of egg particles, laid as an egg, that result from infection within a hen’s oviduct. It is technically known as caseous exudate — in other words cheesy discharge.

Leg Band
A plastic or aluminum ring that wraps around a chicken’s leg for the purpose of identification.

Lethal Gene
One of more than 50 different genes that result in a a chicken’s death, typically as an embryo during incubation. One such gene is associated with the Araucana chicken’s tufted trait.

Small, wingless, parasitic insects that live on chickens and irritate them by chewing their skin.

Light Breed
A large chicken breed (not a bantam) that is more slender than round, and in which hens usually weigh 4.5 pounds or less and roosters weigh 6 pounds or less.

Loose material (such as wood shavings) scattered on the floor of a chicken coop to absorb moisture and droppings, cushion the birds’ feet, and provide insulation.

Long Crower
One of several chicken breeds, such as Denizli, that are bred specifically for the tone and duration of the rooster’s crow.

Long Tail
One of several chicken breeds — including Yokohama and Phoenix — that are prized for having particularly long tail feathers.

– M –

Mail-Order Chicks
Chicks that are shipped by mail immediately after they hatch, while they are still absorbing residual yolk as nourishment until they reach their destination.

Marek’s Disease
A viral infection that affects mainly the nerves of growing chickens, causing paralysis and and sometimes death.

Marek’s Vaccine
A vaccine that prevents paralysis caused by Marek’s disease, but does not prevent chickens from getting the disease and shedding the virus.

Mating Ratio
The optimal number of hens available for each rooster in the flock to ensure good fertility.

Meat Breed
A chicken breed or hybrid developed for rapid growth and heavy muscling.

A tiny spiderlike body parasite, related to the tick, that survive by eating a chicken’s skin, feathers, or blood.

The annual shedding and renewal of plumage that typically occurs in the fall, before the arrival of cold weather.

A measure of the number of chickens in a given flock that come down with a particular disease.

A measure of the number of chickens in a given flock that die from a particular disease.

– N –

National Poultry Improvement Plan
The National Poultry Improvement Plan (NPIP) is a nationwide collaboration between state and federal departments of agriculture designed to monitor member flocks and hatcheries and certify them as being free of a number of serious infectious diseases.

The examination of a dead chicken in an attempt to determine why it died (equivalent to a human autopsy).

Nest Box
A manufactured nest provided as a place for hens to lay eggs where they may easily be found.

Nest Egg
A fake egg placed in a nest to encourage hens to lay their eggs in a nest box.

Nest Pad
A sheet of thick material designed to fit into the bottom of a nest box to keep it clean and prevent eggs from getting broken.

Nipple Drinker
A small conical device inserted into a water pipe or water bucket that, when pecked by a chicken, releases a few drops of water for the chicken to drink.

Northern Fowl Mite
A dark red or black mite that feeds on chickens, causing itchy scabby skin and darkened feathers around the vent.

Not Show Quality (NSQ)
A chicken that is unsuitable for exhibition, although it may be breeder quality or pet quality.


Open Show
An exhibition at which poultry owners compete regardless of their age, as distinct from a Youth Show.

The mating of chickens that are not directly related.

Undeveloped egg yolks which, when fertilized by a rooster, are able to develop into embryos.

One unit in a cluster of ova, each of which is a hen’s unfertilized reproductive cell.

The reproductive organ containing a hen’s ova.

A passageway extending from a hen’s ovary, down which each developing egg descends on its way to being laid.

– P –

Also called pasty butt, pasting is a fairly common condition in chicks that have soft poop sticking to the vent area.

A microscopic organism that causes disease.

Pathology Lab
A laboratory at which necropcies are performed. Each state has at least one state-run lab, which may be called a veterinary or animal disease diagnostic laboratory.

Pecking Order
The social ranking of individuals in a flock that determines, for example, which chickens eat first and which ones roost on the highest perch.

Rod-shaped pieces of compressed feed, each small piece of which contains the feed’s complete nutritional balance.

Pet Quality
A healthy chicken that is not a high egg producer or does not conform well enough to its standard description to be of show quality.

The pinlike tip of a freshly emerging feather that appears when a chick develops its first true feathers, and later, whenever it molts.

The small hole a hatching chick makes in its shell in an effort to break free. Also the process of making the hole.

The entire collection of feathers that cover a chicken’s body.

Point of Lay
The time at which a pullet lays her first egg.

Pop Hole
A small chicken-size door through which chickens exit and enter their coop.

Preen Gland
A gland at the base of a chicken’s tail that secretes oil the chicken rubs over its feathers while preening.

A chicken’s grooming behavior involving realigning the feathers and protecting them with preen oil.

Premium List
A list of the classes to be exhibited at a particular show, along with the prizes (premiums) to be awarded.

Primary Feathers
The 10 longest feathers on a chicken’s wing.

A young female chicken that’s less than one year old.


The degree to which a chicken conforms to the standard for its breed and variety, which may be show quality (SQ), not show quality (NSQ), breeder quality (BQ), or pet quality (PQ).

The base of a feather shaft that attaches the feather to the chicken’s body.

– R –

Rare Breed
A rare breed is one that is not used in large-scale commercial agriculture but is kept primarily to prevent loss of the breed’s unique genetic traits.

Red Mite
A mite that feeds on chicken blood, potentially causing lethargy and anemia.

A rooster.

A perch, typically inside a chicken coop. Also the act of perching.

Lacking a tail, a feature that is characteristic of Araucanas and is associated with reduced fertility.

– S –

The part of a chicken where the back joins the tail.

Scaly Leg Mite
A tiny mite that lives under the scales on a chicken’s legs and feet, leaving debris deposits that raise the scales and irritate the chicken.

Self Color
A uniform single color of plumage in varieties that breed true, as opposed to resulting from the mating of a hen and rooster that differ from each other in color.

Self Sufficient Breeds
Chicken breeds that forage aggressively and otherwise are low maintenance compared to most other breeds. The best example is Old English Game.

Newly hatched chicks that have been sorted according to gender, rather than being straight run.

The part of a chicken’s leg between the hock and the toes.

Show Quality
A chicken that sufficiently conforms to the standard description for its breed and variety to favorably compete at a poultry exhibition.

A rooster’s long, thin tail feathers.

Sour Crop
Sour crop is a fungal infection in a chicken’s upper digestive tract.

Splayed Leg
A condition in newly hatched chicks where the legs slide out to the sides so the chick can’t stand or walk. A common cause of this condition is brooding chicks on a smooth surface that’s too slick for the chicks’ feet to get a grip.

Spur Trimming
Blunting the hard, sharp tip of a chicken’s spurs to prevent injury to itself and others.

The American Standard of Perfection. Also any chicken, whether full size or bantam, that conforms to the description of its breed and variety in the American Standard of Perfection.

Straight Run
Newly hatched chicks that have not been sorted by gender, but remain in the same percentage as they hatched, which may or may not be 50/50.

A bloodline (or “line”) of related chickens, the pedigree of which has been established after generations of being selectively bred for specific traits.

Any physical or emotional tension that reduces a chicken’s resistance to disease and can decrease egg production. Common causes of stress are overcrowding, distrupting the pecking order, improper diet, and not enough clean drinking water.

– T –

Table Egg
An egg intended for human consumption, rather than for hatching.

Sour crop.

Activity typical of roosters and mother hens whereby they repeatedly pick up and drop a piece of food while sounding short high-pitched notes known as the food call.

Toe punch
A small hand-held device used to punch holes into the webbing of a chick’s feet for purposes of identification.

A series of fast steps a rooster makes on a hen’s back during mating.

True Bantam
A small breed of chicken that lacks a larger counterpart. Examples include Bearded d’Anvers, Rosecomb, Sebright, and Serama.

A chicken’s size and shape that tell you which breed it is.


Straight run chicks, not sorted by gender, but remaining in the same percentage of male and female as they hatched.

White semi-solid waste that is the chicken’s equivalent of a human’s liquid urine.

– V –

A subdivision of a breed based on differences in comb, plumage color, or other physical features.

The outer opening of a chicken’s cloaca.

Vent Sexing
Traditional method of determining a chick’s gender by looking for minor differences in the tiny cloaca, which is inside a chick’s vent.


Red or purplish flaps of flesh that dangle under the beak of many chicken breeds, and that are especially large on some roosters.

Wing Clipping
Shortening the flight feathers of one wing to keep the chicken from flying out of its enclosure.


The yellow-orange pigment that colors egg yolks, and also the skin and shanks of some chicken breeds. Sources include marigold petals, leafy greens, and yellow corn.


Yolkless Egg
An egg consisting of a shell filled with albumen, but no yolk, often laid by a pullet as her first egg, or by a hen at the end of a laying cycle or the beginning of a new cycle.