simian /ˈsɪm.i.ən/adjective 2noun 1forms 3 adjective2 •Of or pertaining to apes and monkeys. •Bearing resemblance to an ape or monkey; apelike or monkeylike. noun1 •An ape or monkey, especially an anthropoid (infraorder Simiiformes).The simians would require no special orientation courses to teach them the reasons for fighting, such as, “To make the world safe for Demagocracy,” or whatnot. — 1959 formssimians · more simian · most simian