[ proh-thawr-aks, -thohr- ]

noun,plural pro·tho·rax·es, pro·tho·ra·ces [proh-thawr-uh-seez, -thohr-]. /proʊˈθɔr əˌsiz, -ˈθoʊr-/.
  1. the anterior division of the thorax of an insect, bearing the first pair of legs.

Origin of prothorax

From New Latin, dating back to 1820–30; see origin at pro-1, thorax

Other words from prothorax

  • pro·tho·rac·ic [proh-thaw-ras-ik, -thoh-], /ˌproʊ θɔˈræs ɪk, -θoʊ-/, adjective Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use prothorax in a sentence

  • The prothoracic feet of the male are small and weak; of the female, stronger.

    The Butterfly Book | William Jacob Holland
  • The prothoracic legs of the males are smaller than in Basilarchia.

    The Butterfly Book | William Jacob Holland
  • The head is moderately large, the eyes hairy, the palpi more or less heavily scaled, the prothoracic legs feeble and hairy.

    The Butterfly Book | William Jacob Holland
  • Prothoracic bristle: in Diptera, a strong bristle immediately above the front coxa: see propleural bristles.

  • Prothoracic glands: occur in Orthoptera, on the sides of prothorax in certain Phasmid genera.

British Dictionary definitions for prothorax


/ (prəʊˈθɔːræks) /

nounplural -thoraxes or -thoraces (-ˈθɔːrəˌsiːz)
  1. the first segment of the thorax of an insect, which bears the first pair of walking legs: See also mesothorax, metathorax

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012