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Medicine & BodyGreekEnglish

Mastoid

/ˈmæstɔɪd/adjective

Relating to the bony bump behind the ear.

The Greek roots

μαστός
mastós
breast, nipple
+
εἶδος
eîdos
form, shape

Literally: breast shaped

The story of the word

The bone was named for its nipple-like bulge, which you can feel by pressing behind your earlobe. The same root gives mastitis and mastectomy. It also gives the mastodon: early nineteenth-century anatomists saw nipple-shaped cusps on the fossil teeth and named the whole animal breast-tooth.

How it travelled
Ancient Greek → Modern Latin → English
First recorded
18th century

Same family

mastectomymastitismastodon

In a sentence

Before antibiotics, an ear infection could eat into the mastoid and kill.

Built on the same root

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