simulator n.

1835, of persons, "one who simulates or feigns" (illness, sanctity, etc.), from Latin simulator "a copier, imitator," agent noun from simulare "to make like, imitate, copy, represent," from stem of similis "like, resembling, of the same kind" (see similar). In reference to training devices for complex systems, from 1947 (flight simulator). Related: Simulatory.