triennium/trieʹeni·əm/ noun (pl trienniums triennia /-ni·ə/)

• counter
• counter-
• counteract
• counterattack
• counterattraction
• counterbalance
• counterblast
• counterchange
• countercharge
• counterclaim
• counterclockwise
• counterculture
• counterespionage
• counterexample
• counterfactual
• counterfeit
• counterfoil
• counterinsurgency
• counterintelligence
• counterintuitive
• counterirritant
• countermand
• countermarch
• countermeasure
• countermove