BEM

from Fancyclopedia 2

(Alger) Initialese for that stock stfnal character, the Bug Eyed Monster, Symbolic of the "middle period" [starting about 1937] and juvenile type of magazine stf, which stirs up the emotions more than the intellect, performs simple transmutations of known and unknown, and makes few concessions to plausibility. Coined indirectly in the August 1939 TWS, when Martin Alger parodied the alphabet organizations of the Staple War by announcing the formation of the Society For Prevention Of Bug Eyed Monsters On The Covers Of Science Fiction Publications and later, January '41, had a letter published which first refers to the cover-critturs as BEMs. It became the first piece of strictly fan slang to get into a mundane dictionary when Funk & Wagnalls included this valuable word, defining it as "various abhorrent monsters, such as are found in science-fiction".