Widening rhymes with:
abandoning, broadening, burdening, clendening, deadening, gardening, glendening, hardening, maddening, pardoning, saddening
Widening sounds like:
wadhams, wading, waiting, wedding, weddings, weeding, wetness, wetting, whitenack, whiteness, whitening, whiting, whitings, whitman's, whitney's, whitting, widens, widing, wieting, witness, witness', witness's, witnesses, witnesses', witting, woodhams, wooding, woodmac, woodmansee