Diffusing rhymes with:
defusing, defusing, confusing, defusing, fusing, infusing, refusing, suffusing, abusing, accusing, amusing, confusing, defusing, excusing, fusing, infusing, misusing, musing, overusing, recusing, refusing, reusing, suffusing, using
Diffusing sounds like:
debasing, debugging, defacing, defeasance, deficiencies, deficiency, defusing, devising, division's, divisions, divisions', dobkins, dobson's, dobsons