WordDictionary

Noun:

• botany|countable A cellular outgrowth of the epidermis, consisting of one or of several cells, whether pointed, hooked, knobbed, or stellated. Internal hairs occur in the flower stalk of the yellow frog lily (Nuphar).
• countable|uncountable A pigmented keratinaceous growth that forms thin spires and grows out from a follicle on the human head, or the collection of them.
• zoology|countable A slender outgrowth from the chitinous cuticle of insects, spiders, crustaceans, and other invertebrates. Such hairs are totally unlike those of vertebrates in structure, composition, and mode of growth.
• countable Any very small distance, or degree; a hairbreadth.
• obsolete A haircloth. - Geoffrey Chaucer
• uncountable The collection or mass of filaments growing from the skin of humans and animals, and forming a covering for a part of the head or for any part or the whole body.