anacronym
n. An acronym where few people remember what each letter stands for (anachronistic + acronym).

Example Citations:
The alliance is known as the OSHA/ Environmental Network, which includes groups such as the United Auto Workers, the Chemical and Atomic Workers Union, the Sierra Club and the American Lung Association of New Jersey. (OSHA is the anacronym for the Federal Occupational Safety and Health Administration.)
—Leo H. Carney, “Environews,” The New York Times, July 3, 1983

AHEPA, an anacronym standing for the American-Hellenic Educational Progressive Association, was originally founded in 1922 in Georgia to aid Hellenics earn American citizenship.
—Celestine Bohlen, “Governor sworn in to Lowell AHEPA,” The Lowell Sun, March 30, 1975

Earliest Citation:
NAYRU is an anacronym that has been mouthed by racing sailors since 1898. The letters stand for North American Yacht Racing Union, the governing body for all yacht racine in the U. S. and Canada.
—Almon Lockabey, “U. S., Canada Start Own Sailing Groups,” Los Angeles Times, March 21, 1975

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