Capon is a portmanteau of "cockerel" and "castrated". The word has been used in English since the 15th century. It comes from Old French "capon", from Latin "caponem" (originally from the Ancient Greek κάπων), which itself comes from the Late Latin "capo" ("head"), and is a variant of "cappōnem" / "ca(p)pawnem", which derives from the older Latin word. Capons are different to other male chickens.
The meat of young cockerels is often considered to be a delicacy in many parts of the world, including China, Mexico, and Italy. Most modern capon production involves inducing an artificial "masculinization" of the chicken; this includes injecting the bird with testosterone and then using other drugs to counteract the effects of the testosterone.
Capons gain weight faster and produce more tender meat than ordinary cockerels, and as such, they are bred on a large scale in intensive caponizing systems, which now dominate farming for this reason. A consequence of these modern breeding practices is that most capons share the same genotype, and genetic differences between capons and other chickens are mainly observable at the chromosomal level.
Capons were formerly valued more highly than mere cockerels in France, for their perceived greater succulence, however, they have fallen greatly out of favor there since 1950 due to their high price. The traditional method of caponization results in a partial sex reversal: the roosters do not develop the combs and wattles of true roosters, but never obtain hen-like plumage.
The lack of comb and wattle is considered desirable by some diners, so capons are often marketed with these body parts removed. Another method is chemical caponization, which involves injecting the bird with estrogen, resulting in a sex-reversed bird.
Capon is regarded as one of the highest quality poultry meat and became widely available and popular across Europe and later the Commonwealth beginning in the early 16th century owing to technological improvements in farming such as artificial lighting, temperature controls, and building arrangements.
In the 17th century, numerous capon varietals were created through selective breeding in France, such as "the Roman capon" with a melodious call named for its origins in Roman chickens imported from Greece. The Roman breed was preferred by wealthier Europeans for meat because of their soft feathers which meant their carcasses could be more easily plucked.
In traditional poultry farming systems, capons were usually given access to the outdoors on grass where they would range and feed for most of the day. Capons can fly as well as walk and despite a report that about half of the daily food intake is from foraging, a capon's diet often places it at odds with its natural tendency to do so. The "Encyclopedia of Poultry Breeds" lists as primary breeds used for caponization the New Hampshire, the White Crested, White Laced Red, Croad Langshan, Ancona, and the Leghorn.