The act of barfing and having intense diarrhea simultaneously; given this name because it is similar to being shredded at both ends, as a ninja would do.
John: That mexican food last night was rotten
Ryan: I know, I ninja'd all over the bathroom floor when i got home.
Ryan: I know, I ninja'd all over the bathroom floor when i got home.
by TheShredder April 05, 2011
Get the Ninjamug.