An attack made in response to an attack by the opponents(noun)
To attack in response to an attack by opponents(verb)
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Use "counter-attack" in a sentence
"But troops loyal to President Ali Abdullah Saleh have launched a counter-attack to try to regain control of the city."
"That is why the senate and house (Dems and Rep) rubber stamped the war in Iraq, instead of questioning the information; we just got attacked and if they voted against a counter-attack they would lose votes."
"With every intimidation tactic, Chicago added more intensity to their counter-attack."