noun; a girl who frequently posts only attractive pictures of herself on social media, especially instagram, in order to gain attention and self-validation from strangers on the internet
Guy 1: Hey man, have you met Lexi? I thought she was pretty cool when I met her in person but then I found her on Instagram and realized she was a instagir.

Guy 2: Good luck with that buddy. She already has the interest of every dude on social media.
by Tyneous April 15, 2017
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