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1.
1. When someone hits the nail on the head with a comment or comeback, the appropriate response by any participating spectator should be "rockabye".

2. When someone makes a suggestion that is simply outstanding, the appropriate response is "rockabye". Sort of similar to "amen" if you will.
Person 1: "Let's get wasted tonight!"
Person 2: "Rockabye!"

by Libby G. May 24, 2006