1 definition by Some who knows!

A mother of a mother. If she has grandchildren , then she is a builtin free baby-sitter and or someone that can help or watch your children for you , since they don't have anything else to do.
Mother: Hey mom what are you doing tonight?

Grandma: Nothing just watching NCIS

Mother: Then can you watch Timmy for me ?

Grandma: What are you doing? Yes I can
by Some who knows! January 27, 2014
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