duke n.

Proto-Indo-European root meaning "to lead."

It forms all or part of: abduce; abducent; abduct; abduction; adduce; aqueduct; circumduction; conduce; conducive; conduct; conductor; conduit; deduce; deduction; dock (n.1) "ship's berth;" doge; douche; ducal; ducat; Duce; duchess; duchy; duct; ductile; duke (n.); educate; education; induce; induction; introduce; introduction; misconduct; produce; production; reduce; reduction; seduce; seduction; subduce; subduction; taut; team (n.); teem (v.1) "abound, swarm, be prolific;" tie (n.); tow (v.); traduce; transducer; tug; zugzwang.

It is the hypothetical source of/evidence for its existence is provided by: Latin dux (genitive ducis) "leader, commander," in Late Latin "governor of a province," ducere "to lead;" Old English togian "to pull, drag," teonteon "to pull, drag;" German Zaum "bridle," ziehen "to draw, pull, drag;" Middle Welsh dygaf "I draw."

Old English eorl "brave man, warrior, leader, chief" (contrasted with ceorl "churl"), from Proto-Germanic *erlaz, which is of uncertain origin. In Anglo-Saxon poetry, "a warrior, a brave man;" in later Old English, "nobleman," especially a Danish under-king (equivalent of cognate Old Norse jarl), then one of the viceroys under the Danish dynasty in England. After 1066 adopted as the equivalent of Latin comes (see count (n.1)).

Earl Grey tea (1880s) was originally a Chinese tea blended with bergamot oil, supposedly from a recipe given to Charles, second Earl Grey (the Whig prime minister), in the 1830s, but perhaps it was named later, commercially, in his honor.