Untested rhymes with:
uncontested, uncontested, attested, detested, retested, uncontested, attested, bested, detested, divested, guested, molested, rearrested, reinvested, requested, retested, uncontested, unmolested, wrested
Untested sounds like:
unadjust, unadjusted, unattached, undecided, undetected, undisguised, uneducated, unhedged, unindicted, unmatched, unmitigated, unnoticed, untaxed, untouched