ad·ver·sary 
/ˈædvɚˌseri, Brit ˈædvəsri/ noun
plural ad·ver·sar·ies /ˈædvɚˌseri, Brit ˈædvəsri/ noun [count] formal : an enemy or opponent
▪ His political adversaries tried to prevent him from winning the nomination.
▪ His political adversaries tried to prevent him from winning the nomination.
