Also found in: Thesaurus, Encyclopedia.


 (rĭ-trôrs′, rē′trôrs′)
Directed or turned backward or downward.

[Latin retrōrsus, from retrōversus : retrō-, retro- + versus, past participle of vertere, to turn; see wer- in Indo-European roots.]

re·trorse′ly adv.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(Botany) (esp of plant parts) pointing backwards or in a direction opposite to normal
[C19: from Latin retrōrsus, shortened form of retrōversus turned back, from retro- + vertere to turn]
reˈtrorsely adv
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ˈri trɔrs)

turned backward.
[1815–25; < Latin retrōrsus, contracted form of retrōversus bent backward]
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Adj.1.retrorse - bent or curved backward or downward; "leaves with retrorse barbs"
biological science, biology - the science that studies living organisms
antrorse - bent or curved forward or upward; "a plant having antrorse hairs on the stem"
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
References in periodicals archive ?
S7 with apical lobes narrow, parallel-sided, retrorse section of apex comma-shaped; gonostylus slender in profile, slightly tapering towards apex, basally strongly protuberant on medial margin in dorsal view (Colombia: Antioquia) A.
+ (present);--(absent); Ob (obtuse); rd (round); Ac (acute); Ov (ovate); api (apiculate); El (elliptic); Obv (obovate); An (antrorse); pt (patent); rt (retrorse).
Aedeagus curved ventrad, bent in "C" shape, shaft slightly compressed, with small retrorse spines, abruptly narrowing at distal fourth; phallotrema subapical on dorsolateral surface; periandrum as a transverse strut obtusely bent caudally against the phallotheca, periandrum and anal segment in close contact; connective long, stout, shortly braced to the periandrum above tectiform structure.
Males with one or two small, retrorse bony hooks per segment on first to seventh or eighth segmented rays.
Lip fleshy, flat, unguiculate; the claw semi-cylindrical, with a longitudinal keel, 2-3 mm long; blade 3-lobed, ovate-sagittate, sometimes convex; lateral lobes auricled, retrorse, 1.6 mm long and wide; mid-lobe broadly ovate-peltate, emarginate and minutely apiculate, 5 x 6 mm; callus narrowly triangular to long-acuminate, acute, 2 mm long.
Prosternal spine short, blunt, conical, retrorse; interval between mesosternal lobes subquadrate, the metasternal lobes attingent over a short space.
In many species, the perianth parts are reduced to bristles or setae with retrorse prickle hairs.
[5] Anterior retrorse process of lateral ethmoid (Costa 1990) (CI: 1.00; RI: 1.00): (0) short; (1) moderate to elongate.
armasi by the shape of the fixed chelal finger teeth which are long and erect in the two Cuban species, but short and retrorse in P.
The elongated tapering spine consists of a thin outer layer of enamel-like material, an inner core of vasodentine, and retrorse serrations along the lateral margins.