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1 definition by IncrediblyAwesomePerson

 
1.
To be annoying, stupid, etc. Lumpatious is usually used as an insult to someone who thinks they are the best thing since sliced bread.
(Random Guy) "Duuuude I'm soooo awesome!"
(Other Guy) "STOP BEING SO LUMPATIOUS!!!!"
by IncrediblyAwesomePerson January 13, 2014