fiber
Pluralfibers (some meanings)
UK spellingfibre
- 1A material that takes the form of long, thin strands.
Manufacturers blend several kinds of fiber to make a durable rope.
The insulation relies on a dense fiber that traps warm air.
- 2A single long, thin piece of material, roughly round across, often twisted with others to form thread.
Under the microscope, a single fiber looked perfectly smooth and even.
Workers spin thousands of fibers together into one continuous thread.
Similarstrand, filament, thread
Note
The countable sense the others grow from, written in its US spelling; the word came through French from Latin fibra. It takes an article and a plural (a single blue fiber, two fibers), and that is what separates it from fiber as a material, where cotton or wool is spoken of as a mass. Under a microscope, one strand on a shoe sole is this sense exactly.
- 3The indigestible part of plant-based foods, valued for supporting healthy digestion.
Doctors recommend getting plenty of fiber from fruits and vegetables.
A diet low in fiber can lead to digestive problems.
Note
In everyday talk about food, fiber is short for dietary fiber, and the adjective is almost always dropped: a good source of fiber, high in fiber, a low-fiber diet. Nutrition writing divides it into soluble and insoluble kinds. Both pass largely intact through the small intestine, which is why fiber is linked with digestion rather than with energy.
- 4Inner strength of character and the resolve to do what is right.
Like the steel reinforcement inside concrete that lets it bear great strain.
Facing the scandal honestly revealed the fiber of his character.
Only someone of strong moral fiber would have refused the bribe.
Similarbackbone, strength, mettle, integrity, grit
Note
A figurative transfer from the single strand: what holds a rope together is taken as what holds a person together. Fiber in this sense is tested or shown rather than counted, as in a test of everyone's fiber. Its most natural partner is moral, so a person of strong moral fiber is the phrase most readers will meet.
- 5A long, tube-shaped cell found in bodily tissue, as in muscle.
The biopsy showed damage to a single muscle fiber.
Under the microscope, each fiber appeared as one long cell with several nuclei along its edge.
Note
In cytology the word follows shape rather than strict anatomy. A muscle fiber is one whole elongated cell, built for contraction, while a nerve fiber is the long signal-carrying process of a nerve cell rather than a cell of its own. The word usually takes a tissue in front of it, and without that modifier a reader may take it for the textile strand.
Practice
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Origin
Borrowed from French fibre, from Old French fibre, which comes from Latin fibra.