A GIMPism is essentially a filter such as lens flare or a spyrogimp or edit such as value invert. It effects how an image looks. The term is only to distinguish between image editing filters and Snapchat filters (Because an alarming amount of people forgot what a GIMPism was.)
howisthisafakename: here's an image
(Image sent)
fatguyenthusiast69: hold on i'll apply some GIMPisms to it later and make it crispy.
The affliction of helplessness. The inability to accomplish anything to to lack of interest or knowledge.
That couch potato is inflicted with gimpism.