killer (noun) killer: murderer
Sinonime: benign,
constructive,
favorable, favoring, gainful, good, good for what ails you, healthful,
helpful,
profitable,
propitious,
salubrious, salutary, serviceable,
toward,
useful,
valuable, what the doctor ordered, wholesome,
worthyAntonime: disadvantageous,
harmful, hurting,
unfortunate, unhelpful, unrewarding