mid-14c., "to crush;" early 15c., "crouch on the heels," from Old French esquatir, escatir "compress, press down, lay flat, crush," from es- "out" (see ex-) + Old French quatir "press down, flatten," from Vulgar Latin *coactire "press together, force," from Latin coactus, past participle of cogere "to compel, curdle, collect" (see cogent). Meaning "to settle on land without any title or right" is from 1800. Related: Squatted; squatting.
early 15c., "crouch on the heels, in a squatting position," from squat (v.)). Sense of "short, thick" dates from 1620s.
c. 1400, "bump, heavy fall," from squat (v.). Meaning "posture of one who squats" is from 1570s; that of "act of squatting" is from 1580s. Slang noun sense of "nothing at all" first attested 1934, probably suggestive of squatting to defecate. Weight-lifting sense is from 1954.