Synonyms for Trojan Horse (same or very similar meaning)
WordNet sense 1 (a subversive group that supports the enemy and engages in espionage or sabotage; an enemy in your midst):
fifth column
WordNet sense 2 (a program that appears desirable but actually contains something harmful):
Trojan
WordNet sense 3 (a large hollow wooden figure of a horse (filled with Greek soldiers) left by the Greeks outside Troy during the Trojan War):
Wooden Horse
From the ODE community, based on WordNet
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