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fiber

noun fi·ber \ˈfī-bər\

: plant material that cannot be digested but that helps you to digest other food

: a thin thread of natural or artificial material that can be used to make cloth, paper, etc.

: material (such as cloth) that is made from thin threads : something made of fibers

Full Definition of FIBER

: a thread or a structure or object resembling a thread: as

a (1) : a slender root (as of a grass) (2) : an elongated tapering thick-walled plant cell void at maturity that imparts elasticity, flexibility, and tensile strength

b (1) : a strand of nerve tissue : axon, dendrite (2) : one of the filaments composing most of the intercellular matrix of connective tissue (3) : one of the elongated contractile cells of muscle tissue

c : a slender and greatly elongated natural or synthetic filament (as of wool, cotton, asbestos, gold, glass, or rayon) typically capable of being spun into yarn

d : mostly indigestible material in food that stimulates the intestine to peristalsis —called also bulk, roughage

: material made of fibers; especially : vulcanized fiber

a : an element that gives texture or substance

b : basic toughness : strength, fortitude

c : essential structure or character <the very fiber of a person's being>

— fi·bered \-bərd\ adjective

See fiber defined for English-language learners

See fiber defined for kids

Origin of FIBER

Middle French fibre, from Latin fibra

First Known Use: 1540

Related to FIBER

Synonyms: backbone, constancy, fortitude, grit, grittiness, guts, intestinal fortitude, pluck, spunk

Antonyms: spinelessness

Other Textiles Terms

batt, bias, brocade, duck, flock, lawn, toile

Rhymes with FIBER

briber, giber, scriber, Tiber

FIBER Defined for Kids

fiber

noun fi·ber \ˈfī-bər\

Definition of FIBER for Kids

: a thread or a structure or object resembling a thread

: plant material that cannot be digested

Medical Dictionary

fiber

noun fi·ber

Medical Definition of FIBER

: a thread or a threadlike structure or object: as a : a strand of nerve tissue : axon, dendrite b : one of the filaments composing most of the intercellular matrix of connective tissue c : one of the elongated contractile cells of muscle tissue

: mostly indigestible material in food that stimulates the intestine to peristalsis—called also bulk, dietary fiber, roughage