non believer (noun) nonbeliever: unbeliever
Sinonime: allay,
alleviate,
appease,
calm,
compose,
conciliate,
cool*, ease,
fill,
lessen, lighten,
lull, make nice, mitigate,
moderate, mollify, pacify, palliate,
placate, pour oil on, propitiate,
quench,
quiet, sate,
satisfy,
soften,
still,
surfeit, sweeten, take the edge off, take the sting out,
temper, tranquilize
Antonime: exacerbate,
upset