Words That Rhyme With "Costly" :

2 syllables:

beastly, chastely, christly, crossly, falsie, faulty, frosty, ghastly, ghostly, gristly, hostly, hotly, istle, justly, lastly, moistly, mostly, motley, mottley, potsy, Priestley, priestly, salty, softly, tautly, vastly

3 syllables:

augustly, compressedly, distressedly, professedly, robustly, unjustly