Slashing rhymes with:
clashing, flashing, lashing, splashing, bashing, caching, cashing, clashing, crashing, dashing, fasching, flashing, gnashing, hashing, lashing, rehashing, smashing, splashing, stashing, thrashing, trashing
Slashing sounds like:
salesman's, salesmen's, silicones, siliconix, slackening, slackens, slackness, slicing, slocan's, slogans, slogging, sloshing, slouching, slugging, sluggishness, sluicing, socializing, squelching, sulking