To become paralyzed, or not really knowing what to do, being scared and just watching.
Man: What do you call this when you see for example, a man is beating the hell out of his wife and you do not know what to do?
*out of nowhere from awkward silence
CB: Uhm, By Stander effect!
Man: Correct, what does it mean?
CB: Uhm *thinks, like your paralyzed or don't know what to do.
by CBystander October 14, 2011
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