In reference to a man's flacid penis. When you are a show-er, your penis is the same length as when you are erect. When you are a "grower", you have the same characteristics of a frightened turtle, who's head hides in it's shell. When you are erect, you penis grows in length. The exception to this rule is Chinese, who are neither "show'ers" or "growers".

And the kryptonite to both types is water, because it doesn't matte if you "show" or "grow", at that point you shrink.
When Aaron was in the locker room, he could not figure out why everyone had such a bigger penis than him. It was only until Kelly told him the difference of what a "Show-er" vs "Grower" was. "Show-er vs Grower"
by Tom.Collins.NYC January 9, 2014
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