the.com/cockerel

A teenage rooster, all crow and no credibility yet.

means A young male chicken, past chick stage but not yet a fully mature rooster.

from Simply 'cock' (the male chicken, from Old English 'cocc', likely echoing the bird's own crowing sound) plus the diminutive suffix '-erel', the same ending tacked onto 'pickerel' (a young pike) and 'mongrel'. That suffix generally marks something smaller, lesser, or not-quite-there-yet — fitting for a bird that's all bluster but still finding its voice.

definition
Male chicken under one year old
the crow
Dawn alarm is pure testosterone, not clock-watching
pecking order
Status with hens is earned through literal fighting
etymology
Diminutive of cock, meaning little male bird
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