Here's what rhymes with slightly.
lightly rightly tightly brightly nightly knightly sprightly sightly sprightlier tritely knightlier sightlier politely uprightly unsightly forthrightly eruditely unsightlier contritely impolitely Words that almost rhyme with slightly
idly ripely widely snidely likely lively iti slyly wryly flighty lithely highly mighty finely icy nicely timely wisely ivy dryly shyly slimy wily blithely ibi ici idee iri wifely limy vilely nightie smiley whitey limey nighty showily styli lichee spryly kindly tiny unlikely ninety mildly psyche wildly blindly shiny tidy almighty spicy widi grimy hyphae spiny feisty spiky sublimely pricey wiki dicey piney piny stymie supinely whiny siree spiry skivvy blimey chivy crikey stripey feistier stymy precisely divinely untimely unwisely benignly chenille vaginae concisely untidy expiry unkindly inquiry enquiry imprecisely bolsheviki