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rostellum

[ro-stel-uh m]
noun, plural ros·tel·la [ro-stel-uh] /rɒˈstɛl ə/.
  1. Biology. any small, beaklike process.
  2. Botany. a beaklike modification of the stigma in many orchids.
  3. Zoology.
    1. a projecting part of the scolex in certain tapeworms.
    2. a part of the mouth in many insects, designed for sucking.

Origin of rostellum

1750–60; < New Latin; Latin: little beak, snout, diminutive of rōstrum snout (see rostrum); for formation, see castellum
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

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British Dictionary definitions for rostellum

rostellum

noun plural -la (-lə)
  1. biology a small beaklike process, such as the hooked projection from the top of the head in tapeworms or the outgrowth from the stigma of an orchid
Derived Formsrostellate or rostellar, adjective

Word Origin for rostellum

C18: from Latin: a little beak, from rōstrum a beak
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
rostellum in Medicine

rostellum

[rŏ-stĕl′əm]
n. pl. ros•tel•la (rŏ-stĕl′ə)
  1. A small beaklike part, such as the hooked projection on the head of a tapeworm.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.