Dan
1940s: from Japanese.
wiktionary
From Middle English dan, daun, dam(“lord”), from Anglo-Norman daun, daunz and Old French dan, dam, from Latin dominus. Doublet of don.
Uncertain.
From Japanese 段(dan).
From the pinyin romanization of the Mandarin pronunciation of Chinese 担(dàn).
etymonline
dan
title of address to members of religious orders, c. 1300, from Old French dan (Modern French dom), from Latin dominus "lord" (source also of Portuguese don, Spanish don, Italian donno), from domus "house" (from PIE root *dem- "house, household").
Dan (1)
familiar form of masc. proper name Daniel.
Dan (2)
name of one of the 12 tribes of ancient Israel or its territory, named for its founder; literally "he who judges," related to Hebrew din "to judge." In the Old Testament, it occupied the northernmost part of Israel, hence its use proverbially for "utmost extremity," as in from Dan to Beersheba (the southernmost region), 1738. Related: Danite.