masc. proper name, from German, literally "protection through victory," from Old High German sigu "victory" (see Siegfried) + munt "hand, protection," from Proto-Germanic *mundō, from PIE root *man- (2) "hand."
masc. proper name, German Siegfried, first element from Old High German sigu "victory," from Proto-Germanic *seges- "victory" (source also of Old Frisian si, Old Saxon sigi, Middle Dutch seghe, Dutch zege, German Sieg, Old Norse sigr, Danish seier, Gothic sigis, Old English sige "victory, success, triumph"), from PIE root *segh- "to hold" (source also of Sanskrit saha- "victory," sahate "overcomes, masters").
Second element from Old High German frithu "peace" (from suffixed form of PIE root *pri- "to love"). Siegfried Line, World War I German fortifications in France, is from German Siegfriedlinie, named for the hero in Wagner's "Ring" cycle.
It is the hypothetical source of/evidence for its existence is provided by: Hittite maniiahh- "to distribute, entrust;" Greek mane "hand," Latin manus "hand, strength, power over; armed force; handwriting," mandare "to order, commit to one's charge," literally "to give into one's hand;" Old Norse mund "hand," Old English mund "hand, protection, guardian," German Vormund "guardian;" Old Irish muin "protection, patronage."
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<a href="https://www.etymonline.com/word/sigismund">Etymology of sigismund by etymonline</a>
Harper, D. (n.d.). Etymology of sigismund. Online Etymology Dictionary. Retrieved $(datetime), from https://www.etymonline.com/word/sigismund