Old English; earliest use found in Beowulf. Cognate with or formed similarly to Old Saxon hetelīk (Middle Low German hētelīk, hētlīk), and (without i-mutation) Old High German hazlīh (Middle High German hazlīch, also hezlīch, hezzelīch, German hässlich), Old Icelandic hatrligr from the Germanic base of hete + the Germanic base of -ly.