Hairy ball
topology
A result in topology stating that a continuous vector field on a sphere is always zero somewhere. The name comes from the fact that you can’t flatten all the hair on a hairy ball, like a tennis ball, there will always be a tuft somewhere (where the tangential projection of the hair is zero). An immediate corollary to this theorem is that for any continuous map f of the sphere into itself there is a point x such that f(x)=x or f(x) is the antipode of x. Another corollary is that at any moment somewhere on the Earth there is no wind.
(2002-01-07)
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- Hairy cell
hairy cell n. White blood cells having multiple processes and characteristically present in hairy cell leukemia where they replace bone marrow.
- Hairy-cell-leukemia
noun 1. a form of cancer in which abnormal cells with many hairlike cytoplasmic projections appear in the bone marrow, liver, spleen, and blood. hairy cell leukemia n. A lymphocytic leukemia, usually originating with B cells, and characterized by splenomegaly and cells with a ciliated appearance in the spleen, bone marrow, liver, and blood. Also […]
- Hairy eyeball
noun a look of disdain or disapproval See stink eye Usage Note slang Related Terms give someone the fish-eye
- Hairy-faced
[hair-ee-feyst] /ˈhɛər iˌfeɪst/ adjective 1. having a face covered with hair.
- Hairy frog
noun 1. a W African frog, Astylosternus robustus, the males of which have glandular hairlike processes on the flanks