Ictinus, fl. 2d half of 5th cent. B.C., one of the greatest architects of Greece. His celebrated work is the Parthenon (447-432 B.C.) upon the acropolis at Athens, which he built with the architect Callicrates as associate. Ictinus also built the temple of Apollo Epicurius at Bassae, near Phigalia, c.430 B.C. and is said to have rebuilt the Telesterion at Eleusis.