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household head; master; host (e.g. of a tea gathering); innkeeper; owner (e.g. of a hotel)
husband
亭主が茶室を整えた。
The host prepared the tea room.
彼は良き亭主として家族を養った。
He supported his family as a good head of household.
茶道では亭主が客をもてなすのが礼儀だ。
In the tea ceremony, it is proper etiquette for the host to welcome guests.