Without a comb; lacking a comb or not having the crest-like structure of a comb.
From comb (Old English camb) plus -less suffix meaning 'without' or 'lacking.' A straightforward compound formed to describe animals or objects missing this structure.
Some chicken breeds are 'combless' (called 'creepers'), which actually helps them in cold climates because the fleshy comb wouldn't freeze and get frostbite!
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