your husband; her husband
head (of a household); proprietor (of a store); proprietress; landlord; landlad…
ご無沙汰ですが、ご主人は元気ですか。
How is your husband?
すみません、ご主人は今お仕事ですか。
Is your husband at work?
ご主人によろしくお伝えください。
Please give my regards to your husband.