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Definition of "cilium" [cil•i•um]

  • A microscopic hairlike process extending from the surface of a cell or unicellular organism. Capable of rhythmical motion, it acts in unison with other such structures to bring about the movement of the cell or of the surrounding medium. (noun)
  • An eyelash. (noun)
  • Botany One of the hairs along the margin or edge of a structure, such as a leaf, usually forming a fringe. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Use "cilium" in a sentence
  • "Unlike the tower of Iacocca Hall, the cilium is a dynamic structure, in which many of its protein parts are actively altered in response to changing internal and external conditions."
  • "The cilium is an elegant molecular machine that powers the swimming of cells as diverse as sperm and pond algae."
  • "Many proteins of the eukaryotic flagellum also called a cilium or undulipodium are known to be dispensable, because functional swimming flagella that lack these proteins are known to exist."