出典:Wiktionary
From Middle English bethen, from 古期英語 beþian, beþigean, beþþan, bæþþan (“to heat, warm, foment, wash, cherish; bathe”), from Proto-West Germanic *baþþjan, *baþigōn, from Proto-Indo-European *bʰeh₁- (“to warm”). Cognate with Middle Dutch betten, bessen (“to moisten with hot water, humidify”).