Here's what rhymes with fluctuatingly.
aggravatingly gratingly irritatingly accommodatingly titillatingly hesitatingly deprecatingly devastatingly fascinatingly penetratingly calculatingly nauseatingly humiliatingly illuminatingly unhesitatingly exasperatingly ingratiatingly intimidatingly invigoratingly excruciatingly infuriatingly Words that almost rhyme with fluctuatingly
ragingly engagingly amazingly basically persuasively unfailingly pervasively scathingly rakishly piratically creatively evasively meditatively animatedly entertainingly unavailingly imitatively abrasively lackadaisically jadedly qualitatively authoritatively algebraically collaboratively exaggeratedly prosaically complicatedly appreciatively legislatively uncomplainingly exasperatedly manipulatively administratively