Fireflies rhymes with:
butterflies, butterfly's, hoverflies, butterflies, butterfly's, gadflies, hoverflies, actualize, alkalies, analyze, annualize, brutalize, butterflies, butterfly's, cannibalize, capitalize, caramelize, catalyze, centralize, civilize, collateralize, commercialize, compartmentalize, creolize, criminalize, crystallize, decentralize, deinstitutionalize, demobilize, demoralize, denationalize, departmentalize, depersonalize, destabilize, editorialize, equalize, evangelize, federalize, fertilize, fictionalize, finalize, formalize, fossilize, gadflies, generalize, globalize, hospitalize, hoverflies, hydrolyze, idealize, idolize, immobilize, industrialize, initialize, internalize, internationalize, legalize, liberalize, localize, maglaj's, marginalize, materialize, memorialize, metabolize, mineralize, mobilize, monopolize, moralize, multiplies, nationalize, naturalize, neutralize, normalize, panelize, paralyze, pastoralize, penalize, personalize, professionalize, radicalize, rationalize, realize, reanalyse, recapitalize, regionalize, renationalize, revitalize, scandalize, serialize, socialize, specialize, stabilize, sterilize, stylize, symbolize, tantalize, tranquilize, trivialize, undercapitalize, underutilize, utilize, vandalize, verbalize, visualize
Fireflies sounds like:
fireballs, fireplace, fireplaces, frivolous