Here's what rhymes with difficilness.
stillness Words that almost rhyme with difficilness
thickness fitness sickness villus business witness vicious richness stiffness citrus fearless viscous bigness dimness hillocks sinless sinuous cirrus minutes visits forgiveness bacillus assiduous eyewitness quickness seditious swiftness thickets billets cystitis discus officious resistless unfitness hibiscus nimbus witless distance religious assistance resistance limits spirits bishops exhibits insistence mistress suspicious delicious digits fictitious inhibits tickets auspicious biscuits brilliance hindrance diffidence elicits frigates grimace listless litmus pickets rivets strictness avaricious pittance pivots beardless bigots litigious pickups riddance snippets wickets windlass windless wingless existence appearance adherence ambitious assistants clearance disappearance persistence subsistence coherence judicious malicious pernicious perseverance shipments distinctness meniscus papyrus trinkets crickets factitious indigence irreligious triplets mastitis profitless solicits interference adherents prodigious superstitious admittance capricious coexistence pigments prestigious prohibits nutritious propitious consistence expeditious incoherence injudicious remittance repetitious surreptitious agribusiness coefficients delinquents adventitious archbishops reappearance reminiscence eucalyptus infringements transmittance endearments nonreligious unambitious commitments contingents nonexistence enlistments unpropitious noninterference