It is a common term, often used when 'grinding my gears' or 'annoying me' have already been used or aren't quite alternative and imaginative enough. Much like the chafing of tight underwear against one's thighs, the chafing of the mind is both annoying and unwanted. When someone's rubbing your brain and leaving a rash, just tell 'em how you feel.
Roy: "Hey mom can I have some money for the bus?"
Mom: "Fuk off Roy. You're really chafing my mind today."
another term for a station wagon, mini-van, or any other kind of vehicle that is targeted at the "family" demographic(also M.A.V.)
"Tactical advantages aside, the M.A.V. is top of the line for the holy warrior troop transport manufactured by the Church of Latter Day Saints Military Industrial Complex. Also great for family trips...to heathen lands."
12 step recovery jargon referring to someone new who talks about how great life is, now that they'resober. Usually meaning that the person is out of touch with reality.
The new guy seems pretty happy for a dude who has no job, no money and no family. He must be on a pink cloud.