Smashing rhymes with:
bashing, caching, cashing, clashing, crashing, dashing, fasching, flashing, gnashing, hashing, lashing, rehashing, slashing, splashing, stashing, thrashing, trashing
Smashing sounds like:
samsung, samsung's, sansing, schmiesing, schmoozing, senescence, sensenig, sensing, sequencing, shenanigans, simkins, singing, sinking, smacking, smoking, smoking's, smoshing, smugness, snacking, snagging, snaking, sneaking, sneezing, snoozing, snugging, squeamishness, ssangyong, sunshine's, swensen's, swinging