the belief that groups of humans possess different behavioural and physical traits corresponding to which month they were born in.
Person A: How old do you think I am?
Person B: Idk, you look like a January guy.
Person A: THAT'S MONTHISM
Person B: Idk, you look like a January guy.
Person A: THAT'S MONTHISM
by Yeeperdoodles May 1, 2020
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