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a combining form meaning “fiber,” used in the formation of compound words: fibrolite.
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Also especially before a vowel, fibr-.

Origin of fibro-

Combining form representing Latin fibrafiber
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2022


What does fibro- mean?

Fibro- is a combining form used like a prefix meaning “fiber” (or “fibre,” in British English). It is often used in medical terms, especially in anatomy and pathology, referring to slender, threadlike parts of nerve, muscle, or connective tissue.

Fibro- comes from the Latin fibra, meaning “fiber, filament, entrails.” Outside of medicine, fiber has a wide variety of senses in areas ranging from botany to optics to chemistry to nutrition, of course. Be sure to get your fill of fiber at our entry for the word.

What are variants of fibro-?

When combined with words or word elements that begin with a vowel, fibro- becomes fibr-, as in fibrin, source of the closely related combining form fibrino-.

Examples of fibro-

One example of a medical term you may be familiar with that features the combining form fibro- is fibromyalgia, “a syndrome characterized by fatigue and chronic pain in the muscles and in tissues surrounding the joints.”

The combining form fibro- means “fiber,” specifically muscle and tissue fiber in this word. Myalgia means “pain in the muscles.” Fibromyalgia literally translates to “muscle fiber pain.”

What are some words that use the combining form fibro-?

What are some other forms that fibro- may be commonly confused with?

Break it down!

The combining form -cyst represents the word cyst, a fluid-containing sac that forms in animal tissues. What part of the body, generally speaking, does a fibrocyst affect?

How to use fibro- in a sentence

British Dictionary definitions for fibro- (1 of 2)

/ (ˈfaɪbrəʊ) /

noun Australian informal
  1. short for fibrocement
  2. (as modifier)a fibro shack
a house built of fibrocement

British Dictionary definitions for fibro- (2 of 2)


combining form
indicating fibrous tissuefibroin; fibrosis
indicating fibrefibrocement

Word Origin for fibro-

from Latin fibra 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

Medical definitions for fibro-


Fiber, especially fibrous tissue:fibrocyst.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.