1. A slender, elongated, threadlike object or structure.
2. Botany One of the elongated, thick-walled cells that give strength and support to plant tissue.
a. Any of the filaments constituting the extracellular matrix of connective tissue.
b. Any of various elongated cells or threadlike structures, especially a muscle fiber or a nerve fiber.
a. A natural or synthetic filament, as of cotton or nylon, capable of being spun into yarn.
b. Material made of such filaments.
a. An essential element of a person's character: "stirred the deeper fibers of my nature" (Oscar Wilde).
b. Strength of character; fortitude: lacking in moral fiber.
6. Coarse, indigestible plant matter, consisting primarily of polysaccharides such as cellulose, that when eaten stimulates intestinal peristalsis. Also called bulk, roughage.
[French fibre, from Old French, from Latin fibra.]
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