osmeterium

American  

[oz-mi-teer-ee-uhm] / ˌɒz mɪˈtɪər i əm /

noun

plural

osmeteria

1. a glandular process on the first thoracic segment of many caterpillars that emits a noxious odor to ward off predators.

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Etymology

Origin of osmeterium

First recorded in 1815–20; from New Latin osmētērium, from Greek osmḗ “odor, smell” + -tērion noun suffix for places and utensils, akin to Latin -tōrium; see -tory ² ( def. )