Here's what rhymes with unextinguishably.
indistinguishably Words that almost rhyme with unextinguishably
physically cynically pitifully extrinsically ubiquitously sadistically iniquitously politically clinically critically empirically statistically mechanistically militantly subliminally scientifically intrinsically metaphysically precipitously uncritically centrifugally pontifically nonphysically significantly citizenry optimistically hypocritically municipally pessimistically parasitically unscientifically chauvinistically hypercritically ritualistically insignificantly nationalistically individualistically