verb

Make (suffering, deficiency, or a problem) less severe.

he couldn’t prevent her pain, only alleviate it

reduce,ease,relieve,take the edge off,deaden,dull,diminish,lessen,weaken,lighten,attenuate,allay,assuage,palliate,damp,soothe,help,soften,temper,control,still,quell,tone down,blunt,dilute,moderate,mitigate,modify,abate,lull,pacify,placate,mollify,sweeten