Lake Trasimenus la·ket·ra·simenus uncommon noun 1. a battle in 217 BC in which Hannibal ambushed a Roman army led by Flaminius SynonymsLake TrasimenusBattle of Lake Trasimenus Related words Broader terms pitched battle Parts Punic War WordNet 2.1 (Princeton University). WordNet 2.1 Copyright Princeton University. All rights reserved.