adj. 25B6; adjective
he was unworthy of trust : UNDESERVING, ineligible, unqualified, unfit.
unworthy behaviour : UNBECOMING, unsuitable, inappropriate, unbefitting, unfitting, unseemly, improper; discreditable, shameful, dishonourable, despicable, ignoble, contemptible, reprehensible.
deserving, becoming.