From Middle English bethen, from Old English beþian (“to heat, warm, foment”), a variant form of baþian (“to bathe”). More at bathe.
beath (third-person singular simple present beaths, present participle beathing, simple past and past participle beathed)
- (transitive, dialectal) To bathe (with warm liquid); foment.
- (transitive) To dry or heat (unseasoned) wood for the purpose of straightening it.