1620s, "feign, pretend, assume falsely" (implied in simulated), back-formation from simulation or else from Latin simulatus, past participle of simulare "to make like, imitate, copy, represent," from stem of similis "like, resembling, of the same kind" (see similar). Meaning "to use a model to imitate certain conditions for purposes of study or training" is from 1947. Related: Simulating.
