That's my MO, add a B to that shit
“M.O.” is an abbreviation for the Latin term modus operandi (1), or “Mode of Operation”—simply put, how you live your life. Wayne’s M.O. is Money Over Bitches (2) (as his chest tattoo states).
Another M.O. is to add a blunt to everything (3). Continuing the weed theme from the two lines above, Wayne’s saying, “When life gives you weed materials, make somethin to smoke on!” And his modus operandi is to add a B to anything to make it better (music, food, sex etc.).
M.O.B. is also slang for the Bloods (4), with whom Wayne is openly affiliated. The Bloods are a gang, or a mob (5)—in other words, a group of people who will beat the shit out of you.
Or Wayne could be saying “That’s my ammo” (6). Any rapper’s best ammunition are his verses, and Wayne’s saying he’s ready to kill with his wordplay, so long as he has a B (beat) to back him up.
Finally, “M.O.” could also mean “my opinion” (7), as in chat slang “IMO,” though this suffers from the “ATM machine” syndrome of the redundant acronym (this is least likely meaning of the seven).
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