Familiar term for an older woman, often used as a vocative with さん or 様. Not used for one's own aunt (see 伯母/叔母).
Ma'am, is there a post office around here?
The old lady next door always gives me sweets.
ma'am; lady; middle-aged woman
Derived from 小 (small, little) and 母 (mother), originally a respectful or affectionate term for an older woman. The exact historical development is uncertain.