OFM, banging on your motherfuckin' FM

from Tyler The Creator (Ft. Jasper Dolphin, L-Boy, Lee Spielman, Left Brain, Lucas Vercetti, Nakel Smith & Taco) – Trashwang Lyrics on Rap Genius

Meaning

An old phrase used in earlier Odd Future releases. OFM = Odd Future Magazine. This brings a nostalgic feel to the album.
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Tyler also says this at the end of “Oldie” and it is mentioned on several other OF-related songs

To help improve the meaning of these lyrics, visit “Trashwang” by Tyler The Creator (Ft. Jasper Dolphin, L-Boy, Lee Spielman, Left Brain, Lucas Vercetti, Nakel Smith & Taco) Lyrics and leave a comment on the lyrics box