Top Definition
A nickname/code word used as an alternative when a girl or woman is on her menstrual cycle or her period.
jane: "hey betty, you wanna come over after school today?"

betty: "nah, i'm having a visit from auntie flo and i don't feel too well about it."
by H.J.S. July 28, 2006

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A colloquial expression for a woman's menstrual cycle.
Auntie flo can also be used in limericks, such as here:

There once was an auntie called flo.
She was sexy and red like Bordeaux.
When she met a vibrator,
She said: come back later,
Cuz today I prefer a regular Joe.
by kinkylimerix January 11, 2015

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Lotsa space for your liquids.

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The Urban Dictionary Mug

Lotsa space for your liquids.

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The Urban Dictionary Mug

Your favorite word on a white mug.

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The Urban Dictionary Mug

One side has the word, one side has the definition. Microwave and dishwasher safe. Lotsa space for your liquids.

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The Urban Dictionary T-Shirt

Soft and offensive. Just like you.

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The Urban Dictionary T-Shirt

Smooth, soft, slim fit American Apparel shirt. Custom printed. 100% fine jersey cotton, except for heather grey (90% cotton).

Buy the t-shirt