The definition of a hectocotylus is a specific arm of a cephalopod that transfers sperm to the female.
(noun)An example of hectocotylus is what a male octopus uses to get a female octopus pregnant.
See hectocotylus in Webster's New World College Dictionary
noun pl. hectocotyli
Origin: ModL < hecto- + Gr kotylē, a hollow, cavity
See hectocotylus in American Heritage Dictionary 4
noun pl. hec·to·cot·y·li (-kŏtˈl-īˌ)
Origin:
Origin: New Latin
Origin: : hecto-
Origin: + Greek kotulē, small cup
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