1. Originating from the music video "#SELFIE" by Chainsmokers, "But first, letmetakeaselfie" is a popular saying used mostly on Vine. It is said right before one takes a selfie; usually taken before one is going to do something --probably something important and/or productive.

2. The most annoying saying ever used on social media, especially on Vine.
1.)
Father: Hey! It's time to go to school!
Daugter: Be right there! But first, letmetakeaselfie. (Dub step)

2.)
Son: Where is Sandra?
Mother: Oh, she's just taking a selfie.
by DrPepperMan March 21, 2014
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