hec·​to·​cot·​y·​lus | \ -ᵊləs\
plural hectocotyli\ -​ᵊlˌī \

Definition of hectocotylus

: a modified arm of a male cephalopod that is specially and variously adapted to effect the fertilization of the eggs especially : an arm that in argonauts and some octopods receives the spermatophores, is inserted into the female mantle cavity, and then is broken free from the body of the male

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History and Etymology for hectocotylus

New Latin, from hect- + -cotylus (from Greek kotylē cup, anything hollow)

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