Here's what rhymes with firefly.
                        
                        
                    
                                lie  fly  fry  ly  rye  sly  lye  wry  lai  luy  slier  by  my  high  why  apply  die  dry  thy  try  y  buy  cry  sky  guy  tie  vi  hi  shy  sigh  bi  bye  chi  dye  fi  hy  nigh  pi  pie  spy  thai  thigh  vie  dei  ply  psi  quae  ty  wir  awry  hai  mai  muy  nai  pry  tri  trie  cy  fy  kai  mei  pri  sy  tai  thei  wai  phi  sty  spry  stye  supply  thereby  rely  hereby  belie  untie  overlie  aquae  amebae  lanai  overfly  reply  deny  imply  nearby  satisfy  whereby  comply  defy  verify  butterfly  alibi  alveoli  samurai  decry  pupae  amoebae  descry  vilify  bonsai  ossify  retry  blowfly  horrify  turfy  scurfy  versify  barfly  hyperbolae  shanghai  ripply  overbuy  occupy  nuclei  specify  alkali  certify  goodbye  underlie  diversify  fortify  nullify  pacify  ratify  unify  falsify  lullaby  termini  terrify  edify  mollify  oversupply  ramify  resupply  acidify  deify  triply  vivify  misapply  stupefy  scarify  vitrify  drachmai  banzais  yuppify  justify  stimuli  clarify  modify  multiply  qualify  classify  signify  simplify  testify  glorify  gratify  notify  purify  amplify  rectify  standby  beautify  solidify  typify  codify  crucify  liquefy  mortify  personify  dragonfly  mystify  stratify  stultify  ultrahigh  calcify  petrify  reunify  revivify  dissatisfy  liquify  mummify  prettify  refortify  speechify  syllabify  identify  magnify  dignify  emulsify  cumuli  beatify  gentrify  dandify  solemnify  exemplify  intensify  quantify  disqualify  objectify  oversimplify  demystify  detoxify  electrify  preoccupy  reclassify  declassify  indemnify  misidentify  transmogrify