Mainly U.S.: medieval vernacular form of Randolf. This was in common use as a given name into the 17th century and gave rise to a surname. In modern use the given name is often a transferred use of this surname.
German: 1. from Middle High, Middle Low German kelle ‘trowel’, hence a metonymic occupational name for a maker or user of such tools. 2. habitational name from any of the places, especially in Rhineland, named Kell, from Middle Low German kel (a field name denoting swampy land), or from kelle ‘steep path’, ‘ravine’ (see Kelle).