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aciculum

[uh-sik-yuh-luh m]
noun, plural a·cic·u·lums, a·cic·u·la [uh-sik-yuh-luh] /əˈsɪk yə lə/.
  1. an acicula.
  2. Zoology. one of the slender, sharp stylets embedded in the parapodia of certain annelid worms, as the polychaetes.

Origin of aciculum

alteration of acicula
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for aciculum

aciculum

noun plural -lums or -la (-lə)
  1. a needle-like bristle that provides internal support for the appendages (chaetae) of some polychaete worms

Word Origin for aciculum

C19: New Latin; see acicula
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