1 definition by boomdog

A childhood condition, usually temporary, in which the afflicted child believes him or herself to be a ninja. This condition typically passes after the child hits puberty and discovers the opposite sex.
Guy 1: Hay bob hows it going.
Bob: Not too bad Guy 1 but my son has ninja syndrome and keeps hiding and throwing stuff at me.
Guy 1: Well thats what you get for deciding to have kids.
Bob: I didn't decide, my wife just didn't get that abortion she said she was
by boomdog July 6, 2014
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