Darkness rhymes with:
harkness, harkness, blackness, bleakness, frankness, harkness, hawkiness, homesickness, likeness, preakness, quickness, sickness, slackness, thickness, uniqueness, weakness
Darkness sounds like:
darkening, dierking, dorgan's, drachmas, dragging, dragon's, dragons, dressing, dressings, drowsiness, drugging, durkheim's