Spandex is a fiber that has had an impact on fashion high and low, casual and formal, outer and under. It's not a trademark, as a number of the names of other fibers are, among them Dacron, Lycra, and Orlon. It's a generic term, coined in 1959 as an anagram of the word expands. Anagrammatic coinages are not common; the only other in our dictionaries that the average person is likely to be familiar with is sideburns. Sideburns is an anagram (and synonym) of burnsides, from Ambrose E. Burnside, a Union general in the American Civil War credited with originating the fashion (in the U.S., at least) also known as side-whiskers.