From Longman Dictionary of Contemporary Englishtantamounttan‧ta‧mount /ˈtæntəmaʊnt/ adjective → be tantamount to something
Examples from the Corpus
tantamount• Critics say the arrangement is tantamount to a dictatorship.• A simple error of judgement was tantamount to artistic suicide.• With Harry, omission was tantamount to deceit.• Forcibly settling the Jarawa would be tantamount to genocide, leading to them being wiped out.• In Michael's mind it was tantamount to mutiny and he would not stand for anyone disagreeing with him.• For campaign strategists, this was tantamount to spinning straw into gold.• At its worst, the life of faith is portrayed in a way that it is tantamount to spiritual repression.Origin tantamount (1600-1700) tantamount “something equal in value” ((1600-1700)), from Anglo-French tant amunter “to amount to as much”