A pre-freshman; a prospective student on a visit(noun)
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Use "prefrosh" in a sentence
"Until the Old Boys changed their minds, she was a Princeton prefrosh."
"“Are you supposed to protect me against vicious squirrels and roving gangs of prefrosh?”"
"It's amazing - and a little scary - that Harvard administrators didn't use some common sense before deciding that this ad for "Harvard's first prefrosh blacklight party" was sufficient grounds for censorship."