noun (1)
fos·​sa | \ ˈfä-sə How to pronounce fossa (audio) \
plural fossae\ ˈfä-​ˌsē How to pronounce fossae (audio) , -​ˌsī \

Definition of fossa

 (Entry 1 of 2)

: an anatomical pit, groove, or depression


noun (2)

Definition of fossa (Entry 2 of 2)

: a slender, long-tailed, carnivorous mammal (Cryptoprocta ferox of the family Eupleridae) of Madagascar that has retractile claws, usually reddish-brown or sometimes black, short, thick fur, and anal scent glands The fossa evolved on the catless island of Madagascar, where it became the ecological equivalent of a cat. With nothing else around to fill the role, the fossa became a sort of mini-leopard, hunting lemurs and other small animals in the forest at night.— Fiona Sunquist

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Illustration of fossa

Noun (2)


In the meaning defined above

First Known Use of fossa

Noun (1)

1733, in the meaning defined above

Noun (2)

1838, in the meaning defined above

History and Etymology for fossa

Noun (1)

borrowed from Medieval Latin, going back to Latin, "ditch, trench," noun derivative from feminine of fossus, past participle of fodere "to jab, dig" — more at fossil entry 1

Noun (2)

borrowed from French, borrowed from Malagasy fosa

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Time Traveler for fossa

Time Traveler

The first known use of fossa was in 1733

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Cite this Entry

“Fossa.” Dictionary, Merriam-Webster, Accessed 22 Sep. 2020.

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More Definitions for fossa


fos·​sa | \ ˈfäs-ə How to pronounce fossa (audio) \
plural fossae\ -​ˌē How to pronounce fossae (audio) , -​ˌī How to pronounce fossae (audio) \

Medical Definition of fossa

: an anatomical pit, groove, or depression the temporal fossa of the skull the fossa in the liver for the gallbladder

Other Words from fossa

fossate \ -​ˌāt How to pronounce fossate (audio) \ adjective

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