Someone who is overly clean-cut, socially awkward and/or lame.

And if the term itself wasn’t insulting enough already, it can be used as an actual clean-cut insult.
“Sally is so weird. She doesn’t know how to interact with people and she never does anything fun. I guess that’s not surprising though since she was homeschooled. She’s literally a banana bread homeschooler.”

“We’re going over to Kevin’s tonight to hang out, you should come.”
“Nah, I’m tired so I think I’m just gonna go home.”
Come on, man. Don’t be a banana bread homeschooler.”
by Urban Power December 13, 2017
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