subtrahend
sub.tra.hend \'s*b-tr*-.hend\ n [L subtrahendus, gerundive of subtrahere] : a number that is to be subtracted from a minuend
Webster's English Dictionarysub.tra.hend \'s*b-tr*-.hend\ n [L subtrahendus, gerundive of subtrahere] : a number that is to be subtracted from a minuend