[ fahy-bruh l, fib-ruh l ]
/ ˈfaɪ brəl, ˈfɪb rəl /


a small or fine fiber or filament.
Botany. any of the delicate hairs on the young roots of some plants.
Cell Biology. any threadlike structure or filament.

Nearby words

  1. fibrefill,
  2. fibreglass,
  3. fibremia,
  4. fibrescope,
  5. fibriform,
  6. fibrilla,
  7. fibrillar,
  8. fibrillary contractions,
  9. fibrillary tremor,
  10. fibrillate

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 Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for fibril

British Dictionary definitions for fibril


fibrilla (faɪˈbrɪlə, fɪ-)

/ (ˈfaɪbrɪl) /

noun plural -brils or -brillae (-ˈbrɪliː)

a small fibre or part of a fibre
biology a threadlike structure, such as a root hair or a thread of muscle tissue
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 fibril



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

Online Etymology Dictionary, © 2010 Douglas Harper

Medicine definitions for fibril


[ fībrəl, fĭbrəl ]


A minute fiber.

The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

Science definitions for fibril


[ fībrəl, fĭbrəl ]

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.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.