What's the opposite of 부인?

ANSWER: 부군

부인 (夫人) is a polite way to refer to another person's wife, and 부군 (夫君) is the polite way to refer to another person's husband.

If you wanted to be especially polite, such as when referring to your boss's wife, to the wife of a social elite, or to the wife of a world leader, you could say 영부인 (令夫人). So, could you also refer to the husband of a world leader by saying 영부군 (令夫君)? I would not because, even though the character 令 (령) can be translated as esteemed, the character has, at least, the connotation of beautiful. For some reason, it would seem strange to say or even imply, "How's your beautiful husband?"

However, you can very politely refer to another person's son and daughter as esteemed son (영식 - 令息) and beautiful (esteemed) daughter (영애 - 令愛).