Here's what rhymes with happiest.
sappiest snappiest nappiest unhappiest scrappiest crappiest Words that almost rhyme with happiest
shabbiest fattiest nattiest catchiest flabbiest rattiest chattiest battiest cattiest gabbiest patchiest scabbiest tattiest crabbiest scratchiest brattiest grabbiest sassiest shaggiest affianced fanciest handiest canniest flashiest sandiest tackiest baggiest jazziest snazziest campiest daffiest gassiest whackiest ambient pantheist angriest nastiest scantiest manliest classiest dandiest trashiest wackiest brassiest splashiest chanciest craggiest draughtiest glassiest lankiest randiest scraggiest grassiest slangiest waxiest bandiest draggiest craftiest crankiest uncanniest draftiest scraggliest gangliest