1670s, "a trick put upon one, a hoax, a fraud, something that deludes or disappoints expectation," a word of uncertain origin. Along with the verb ("to cheat, trick") and the adjective ("false, pretended"), the word burst into use about 1677 according to OED. Perhaps they are from sham, a northern dialectal variant of shame (n.); a derivation suggested by 1734 and which OED finds "not impossible."
The main modern sense of "something meant to be mistaken for something else, something meant to give a false outward appearance" is from 1728 (the verb in the related sense is from 1690s); applied to persons by 1850.
The meaning "false front" in pillow-sham (1721) is from the notion of "counterfeit." Related: Shammed; shamming; shammer. Shamateur "amateur sportsman who acts like a professional" is from 1896. A song from 1716 calls the Pretender the Shamster.
updated on August 03, 2022