I'm not Biden it is a colloquial way of saying "I don't believe you". It's used to express skepticism or disbelief about something someone said. The phrase "not Biden(something)" means "to not accept or believe something as the truth."
by S1eeper July 3, 2023

by THX1180 August 24, 2021

a sweet man who can sometimes be a bitch but Is a better option than a fat-ass dull cheeto at least he has a better form than a orange if you find him you will be surprised vote blue!
Girl:Damn is that a guy he sometimes can be bitch
Boy: Hey girl
Girl:omg He's not racist he must be a biden
Boy: Hey girl
Girl:omg He's not racist he must be a biden
by Yourlocalsenpai/noona October 27, 2020

the president who while not a fully good person is still superior to the last president, donald dump
by tuntch January 8, 2021

by gaybrowbfemale November 7, 2020

by IdkWhat2Use March 11, 2021
