A metaphor for being the best at something that's unimportant or unimpressive. For example: The fastest pitcher who lives at a nursing home is like being the smartest kid on the short bus.

It comes from the special bus designated for retarded people commonly being shorter than the others.
Zack: I'm the best guitar player in town
Me: Whatever, that's like being the smartest kid on the short bus
by Albert_Phish July 17, 2015
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