Senses
大姨妈/ 大姨媽 eldest maternal aunt
the eldest sister of one's mother
大姨妈/ 大姨媽 period
(colloquial) a polite or indirect way to refer to a woman's menstrual period; Aunt Flo
大姨妈/ 大姨媽 auntie
polite term of address for a woman of one's mother's generation