1540s, "to sacrifice, kill as a victim," from Latin immolatus, past participle of immolare "to sacrifice," originally "to sprinkle with sacrificial meal," from assimilated form of in- "into, in, on, upon" (see in-(2)) + mola (salsa) "(sacrificial) meal," related to molere "to grind" (see mallet). Related: Immolated; immolating.