1. master (of a house, shop, etc.)
旅館の旦那が玄関で出迎えてくれた。The master of the inn greeted us at the entrance.
2. husband
だから旦那にだって頼らない。That's why I don't even rely on my husband.
3. sir; boss; master; governor
used to address a male patron, customer, or person of high status
お元気そうで何よりですよ、旦那。Glad to see you're doing well, sir.
4. patron of a mistress, geisha, bar or nightclub hostess; sugar daddy
5. alms; almsgiving; almsgiver
orig. meaning; usu. written as 檀那