A person who doesnt show up in the park or ruins the nice moment in the park by showing up.

The term arrives from "Partypooping"
Nice guy: Hey Lucas, do you wanna come to the park with us tommorrow? its gonna be nice weather...

Lucas: Nah, id rather stay inside and get even more pale.

Everyone: Lucas is such a parkpooper!
by Ronald_Mc_Nuggets March 11, 2014
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