cock proverbially protective of its hens and noted for aggression; the cock traditionally crows at first light or cockcrow, and is used in cockfighting.

A cock is the emblem of St Peter (see Peter1) and St Vitus.
cock-a-doodle-doo used to represent the sound made by a cock when it crows, and from this, a child's name for a cock.
cock and bull story an incredible tale, a false story; the expression ‘talk of a cock and a bull’ is recorded from the early 17th century, and apparently refers to an original story or fable, now lost.
Cock of the North, in a Jacobite song of c.1715, a nickname given to the Duke of Gordon.
cock-of-the-walk reflecting the dominance of the male bird, a person whose supremacy in a particular circle or sphere is undisputed; the phrase is recorded from the mid 19th century.
Cock Robin a familiar name for a male robin, especially in nursery rhymes.
every cock will crow upon his own dunghill everyone is confident and at ease on their home ground. The saying is recorded in English in the mid 13th century. A similar idea is found in Latin of the 1st century ad, in Seneca's ‘gallum in suo sterquilinio plurimum posse [the cock is most powerful on his own dunghill].’ The work, Apocolocyntosis, is a satire on Claudius's deification at his death, and as gallus means both a cock and a Gaul, Seneca is punning on Claudius's provincial origin and interests.
that cock won't fight that won't do; the expression, which refers to cockfighting, is recorded from the late 18th century.