Term used when you have just finished a bong session and can't execute mental or physical task that sober people would.
Example 1;

Steve: hey, can you go to the supermarket and get me some Doritos

Emily: only if you come with me

Steve: i can't i'm Fresh off the Bong

Example2;

Son: hey mom can you help me with my essay

Mom: sorry son I just became a F.O.B

Son: you're shitting me?
by after you bitch January 24, 2012
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