• synonyms


[fahy-bruh l, fib-ruh l]
  1. a small or fine fiber or filament.
  2. Botany. any of the delicate hairs on the young roots of some plants.
  3. Cell Biology. any threadlike structure or filament.
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Origin of fibril

1655–65; < New Latin fibrilla, equivalent to Latin fibr(a) fiber + -illa diminutive suffix
Related formsfi·bril·lar, adjectivefi·bril·lose, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for fibrillar

Historical Examples of fibrillar

  • The nuclear membrane then disappears and fibrillar cell-plasma or cytoplasm invades the nuclear area.

    Darwin and Modern Science

    A.C. Seward and Others

  • Fibrillar muscular twitching of all the muscles of the body are observed.

  • The variation of Nyctotherus ovalis Leidy, and its fibrillar system.

  • (·4 grain), in about two hours; there are fibrillar twitchings of single groups of muscles and narcosis.

  • In a word, it was shown that each central nerve cell, with its fibrillar offshoots, is an isolated entity.

British Dictionary definitions for fibrillar


fibrilla (faɪˈbrɪlə, fɪ-)

noun plural -brils or -brillae (-ˈbrɪliː)
  1. a small fibre or part of a fibre
  2. biology a threadlike structure, such as a root hair or a thread of muscle tissue
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Derived Formsfibrilar, fibrillar or fibrillose, adjectivefibrilliform, adjective

Word Origin for fibril

C17: from New Latin fibrilla a little fibre
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

Word Origin and History for fibrillar



1680s, back-formation from Modern Latin fibrilla, diminutive of Latin fibra (see fiber).

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Online Etymology Dictionary, © 2010 Douglas Harper

fibrillar in Medicine


(fībrə-lər, fĭbrə-)
  1. Relating to a fibril.
  2. Relating to the fine rapid contractions or twitchings of fibers or of small groups of fibers in skeletal or cardiac muscle.
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(fībrəl, fĭbrəl)
  1. A minute fiber.
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The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

fibrillar in Science


[fībrəl, fĭbrəl]
  1. Any of various threadlike fibers or filaments that are constituent parts of a cell or larger structure. Cellulose fibrils are the main component of cell walls in plants. Fibrils make up the contractile part of striated muscle fiber in the body.
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The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.