coun·ter·weight 
/ˈkaʊntɚˌweɪt/ noun
plural coun·ter·weights /ˈkaʊntɚˌweɪt/ noun [count] : a weight that provides a balance against something of equal weight
▪ The crane has a heavy counterweight on the back. — often used figuratively ▪ Their liberal views act as a counterweight to/against the governor's conservatism.
▪ The crane has a heavy counterweight on the back. — often used figuratively ▪ Their liberal views act as a counterweight to/against the governor's conservatism.
