Meaning of hectocotylus

hec•to•cot•y•lus

Pronunciation: (hek"tu-kot'l-us), [key]
— pl. -cot•y•li
  1. a modified arm of the male of certain cephalopods that is used to transfer sperm to the female.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.