To paint over, or otherwise remove, tagging or
graffiti.
Buffing is the opposite of tagging, and is usually done in colors that blend with the original colors present on the tagged surface. Occasionally,
lame buffers will use other, non-matching/blending colors.
Buffing is not typically employed to remove art, except by the
lame.
A: "Hey, did you see
all that lame tagging that went up in the alley last
night?"
B: "No worries, dude, I already buffed over it."
A: "Sweet!"