fiber

American  

[fahy-ber] / ˈfaɪ bər /

especially British, fibre

noun

1. a fine, threadlike piece, as of cotton, jute, or asbestos.

2. a slender filament.

   a fiber of platinum.

3. filaments collectively.

4. matter or material composed of filaments.

   a plastic fiber.

5. something resembling a filament.

6. an essential character, quality, or strength.

   people of strong moral fiber.

7. Botany.

   1. filamentous matter from the bast tissue or other parts of plants, used for industrial purposes.

   2. a slender, threadlike root of a plant.

   3. a slender, tapered cell which, with like cells, serves to strengthen tissue.

8. Anatomy, Zoology. a slender, threadlike element or cell, as of nerve, muscle, or connective tissue.

9. Also called bulk, dietary fiber, roughage.  Nutrition.

   1. the structural part of plants and plant products that consists of carbohydrates, as cellulose and pectin, that are wholly or partially indigestible and when eaten stimulate peristalsis in the intestine.

   2. food containing a high amount of such carbohydrates, as whole grains, fruits, and vegetables.

10. Chemistry. vulcanized fiber.

11. Optics. optical fiber.

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fiber British  

/ ˈfaɪbə /

noun

1. the usual US spelling of fibre

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fiber Scientific  

/ fī′bər /

1. The parts of grains, fruits, and vegetables that contain cellulose and are not digested by the body. Fiber helps the intestines absorb water, which increases the bulk of the stool and causes it to move more quickly through the colon.

2. One of the elongated, thick-walled cells, often occurring in bundles, that give strength and support to tissue in vascular plants. Fibers are one type of sclerenchyma cell.

3. Any of the elongated cells of skeletal or cardiac muscle, made up of slender threadlike structures called myofibrils.

4. The axon of a neuron.

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Other Word Forms

• fiberless adjective
• interfiber adjective

Etymology

Origin of fiber

1350–1400; 1970–75 fiber for def. 9; Middle English fibre (< Middle French ) < Latin fibra filament

Example Sentences

These fibers formed synapses with one another, closely resembling the connections seen in the human brain.

From Science Daily

This design offers a key advantage over conventional hollow-core fibers, which can take months to fill with atomic vapor.

From Science Daily

Demyelination is the process in which the myelin sheath -- a protective, insulating layer surrounding nerve fibers in the brain and spinal cord -- is damaged or destroyed.

From Science Daily

Competitive intensity in fixed broadband is expected to stay elevated in 2026, though slowing fiber rollout and tapering capital expenditure could boost free cash flow for fixed-line operators, he adds.

From The Wall Street Journal

Shoppers increasingly prefer shorter ingredient lists, recognizable components, and products that convey wellness through high protein, high fiber, or gut-health ingredients.

From Barron's

Related Words

• grain
• thread
• tissue