hectocotylus

[hek-tuh-kot-l-uhs]

noun

Zoology.

plural

hectocotyli 

1. a modified arm of the male of certain cephalopods that is used to transfer sperm to the female.

hectocotylus

/ ˌhɛktəʊˈkɒtɪləs /

noun

1. a tentacle in certain male cephalopod molluscs, such as the octopus, that is specialized for transferring spermatozoa to the female

Word History and Origins

Origin of hectocotylus¹

1850–55; < New Latin, equivalent to hecto- hecto- + -cotylus < Greek kotýlē cup

Word History and Origins

Origin of hectocotylus¹

C19: New Latin, from _hecto- + Greek kotulē cup

Example Sentences

One of the octopus’ eight limbs is a “hectocotylus,” we learn, which is used to “transfer sperm packets from the male to inside the cavity of the female.”

Read more on The Verge

The hectocotylus, like many other genitals, is made of soft tissues which are unlikely to be fossilised.

Read more on The Guardian

In each of these cases the male had the standard third right arm hectocotylus as well as an additional one somewhere else.

Read more on Scientific American

Many species mate from afar—to avoid being eaten—with the male reaching his specialized hectocotylus arm into a female’s mantel cavity.

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The male still makes use of his hectocotylus arm, but in this case, he does it from an otherwise risky position right near the female’s mouth.

Read more on Scientific American