Trachypithecus

Trachypithecus (derived from Greek τραχύς, trachýs meaning "rough" and πίθηκος, píthekos meaning "monkey") is a genus of Old World monkeys containing species known as lutungs, langurs, or leaf monkeys.

Cercopithecidae
Greek: kerkos tail;
Pithecia: From Ancient Greek πίθηκος (píthēkos, “monkey”) + -ia.
Trachypithecus: from Greek τραχύς, trachýs meaning "rough" and πίθηκος, píthekos meaning "monkey".