The story
- Proto-Germanic · derived from*bannijaną“to curse, damn”
- Frankish · derived from*bannjan“to proclaim, order or prohibit under penalty”
- Medieval Latin · borrowed frombannimus“we banish, we expel”
- English todaybannimus
Historically, from Medieval Latin bannimus (“we banish, we expel”), from bannō, bandō (“denounce, ban, banish, proclaim, proscribe”, verb), influenced in meaning by bannum (“ordinance, ban”), from Frankish *bannjan (“to proclaim, order or prohibit under penalty”), from Proto-Germanic *bannijaną (“to curse, damn”), *bannaną (“to request”). Cognate with Old High German bannen (“to order under penalty, proscribe, cast a spell on”), ban (“order under penalty”). More at ban.
Etymology from Wiktionary, CC BY-SA 4.0.