When someone immediately forgets what you just said or what they said before you replied.

Due to chats disappearing in snapchat people have no clue what they previously said leading to mass confusion.
Guy1: hey man that party was bomb af

Guy2: yeah I know right

Guy1: what? I forgot what I just said.

Guy2: dude you got that Snapchat syndrome
by SadabNYC March 19, 2017
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Abbreviated as "SNS", Snapchat Syndrome is the spontaneous making of horrid faces due to overuse of the app Snapchat and making said faces. Prevalent in white girl culture, and so far has no cure aside from iPhone quarantine for 6-8 months.
"Hey, if I make ugly faces when you're talking to me, don't take it personally, I have Snapchat Syndrome."
by The Wordsmithy November 14, 2013
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A very serious illness where a person excessively posts snaps of their face while drunk
Jenny: Oh my god, have you seen Saras stories?
Emma: No, why?
Jenny: She got the Snapchat Shit-faced Syndrome and it's bad.
Emma: Oh, the good ole' triple S.
by gokioki aka gogoloco June 11, 2018
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