Aunt Flo (AF)
Definition - What does Aunt Flo (AF) mean?
Aunt Flo (AF) is a euphemism for a menstrual period. It is used to discreetly tell someone that a person is on their period. The abbreviation "AF" is commonly used in online trying to conceive (TTC) and infertility message boards. Sometimes AF is positive as it can be required to initiate infertility treatment and other times AF starting is devastating as it means treatment has not been successful.
Aunt Flo is also spelled Aunt Flow.
FertilitySmarts explains Aunt Flo (AF)
The term Aunt Flo is used to refer to a menstrual period when someone does not want to overtly state that they have their period. This may be used in public situations, when someone is feeling embarrassed about saying the word "period," or to be funny.
An example of a sentence using this term is, "I don't want to go swimming today because Aunt Flo is in town."
The term was coined in reference to unwelcome family members who show up unexpectedly for a visit.