Archosargus probatocephalus arc·ho·sar·gusprobatocephalus uncommon noun 1. large (up to 20 lbs) food fish of the eastern coast of the United States and Mexico SynonymssheepsheadArchosargus probatocephalus Related words Broader terms sparid Parts Archosargus WordNet 2.1 (Princeton University). WordNet 2.1 Copyright Princeton University. All rights reserved.