The Brief: Fronting or frontin' means to act like you're better than you really are.

DEEP DIVE
The term comes from “putting up a front.”
Quit with all the fronting, you ain’t ’round my clique for nothing –A$AP Rocky, “Peso”
Not everyone is fronting for Twitter & Instagram. Some people just worked harder than you did.
— 40 (@40oz_VAN) August 13, 2018