When a male unzips his fly and 'whips out' his penis, thus demonstrating how big he is. This can also refer to any situation where a male takes his dick out.

This expression refers to the legendary press conference where, when asked why the U.S. continued to fight the Vietnam war, President Lyndon Johnson "unzipped his fly, drew out his substantial organ, and declared, 'this is why!'"

For the metaphorical meaning, see dick waggling contest
Spencer: Dude, what do you do when people say that your dick isn't that big?
John: I just whip it out like LBJ, fool.
by Benny Singles November 12, 2007
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