late 15c., from Old French succomber "succumb, die, lose one's (legal) case," and directly from Latin succumbere "submit, surrender, yield, be overcome; sink down; lie under; cohabit with," from assimilated form of sub "under, beneath" (see sub-) + -cumbere "take a reclining position," related to cubare "lie down" (see cubicle). Originally transitive; sense of "sink under pressure" is first recorded c. 1600. As a euphemism for "to die," from 1849. Related: Succumbed; succumbing.