This question was inspired by @topomorto's recent question, If a wife works and her husband stays at home, are 집사람 and 바깥분 still appropriate for “wife” and “husband” respectively? and my answer saying '바깥양반' is used to mean 'husband' in a more honorific way than '바깥분 (사람)'.
I understand '양반 (兩班)' has multiple meanings as follows:
Ruling class or noble person in Koryo and Chosun dynasty. 고려ㆍ조선 시대에, 지배층을 이루던 신분.
A gentle and polite person. 점잖고 예의 바른 사람.
A word used to indicate one's own husband to others. 자기 남편을 남에게 이르는 말.
A word used to call a man in a casual and (sometimes) disrespectful way. 남자를 범상히 또는 홀하게 이르는 말.
Has the word '양반' ever been used to indicate or mean a woman in Korean? If not, what is the reason that Koreans don't use it for women?