|a.||1.||Bearing or covered with hair; made of or resembling hair; rough with hair; hirsute.|
|2.||Very complicated, difficult, or involved; |
|3.||Dangerous or frightening; |
|Adj.||1.||hairy - having or covered with hair; "Jacob was a hairy man"; "a hairy caterpillar"|
hairless - having no hair or fur; "a Mexican Hairless is about the size of a fox terrier and hairless except for a tufts on the head and tail"
|2.||hairy - hazardous and frightening; "hairy moments in the mountains"|
|1.||hairy - Annoyingly complicated. "DWIM is incredibly hairy."|
|2.||hairy - Incomprehensible. "DWIM is incredibly hairy."|
|3.||hairy - Of people, high-powered, authoritative, rare, expert,
and/or incomprehensible. Hard to explain except in context:
"He knows this hairy lawyer who says there's nothing to worry
about." See also hirsute.|
The adjective "long-haired" is well-attested to have been in slang use among scientists and engineers during the early 1950s; it was equivalent to modern "hairy" and was very likely ancestral to the hackish use. In fact the noun "long-hair" was at the time used to describe a hairy person. Both senses probably passed out of use when long hair was adopted as a signature trait by the 1960s counterculture, leaving hackish "hairy" as a sort of stunted mutant relic.
|4.||(topology)||hairy - hairy ball.|