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1.
Adjective: The attitude one exudes when having menstrual cramps, and being grumpy (ill-tempered, irritable, grouchy) because of it: Grampy.
Example: Sorry I was so Grampy this morning, baby, but I have PMS, and my cramps are really bad today.
by Fatboy67 September 28, 2013
 
2.
noun: one, usually being a grandpa, who excels are barbecuing.
My Grampy will BBQ for you!
by suckafishhh November 16, 2008
 
3.
Grampy is another way of saying Grandpa or Grandfather
My grandparents are called Grampy and Nana
by HolmbergHeart January 14, 2012