One of the guys at work constantly uses this phrase. I’m not sure what he means. He’s a brit, so maybe it is british slang. But maybe not.
Can anyone enlighten me?
Well, in my line of work, if someone tells me that their butt is itching, it usually means that their butt is itching.
Is it possible that this person is a frustrated diagnostician?
Clarification please. Does he say “your butt is itching mean” or “your butt is itching”?
You’re really wanting something. Yer butt is itching to go.
Perhaps he has a hemorrhoid detector?
If he bitches about workload, overtime or countless other issues, tell him his string is showing. 
Perhaps he’d just like to scratch your ass?
If you ask him, please let us know. Now I’m curious.
If the “mean” is part of the phrase, maybe it’s just an unnecessary extra word meaning something like “verily” or “a lot.”
Well, in Chinese, the rhetorical question “does your butt itch?” is asked by parents to misbehaving children – the spanking equivalent of saying they’re “cruisin’ for a bruisin’”.
If he is like one of my co-workers, it is simply explained. He lives in a bubble of his own wonderfulness and that is all the reason he needs to say nonsensical crap. All. Day. Long.
Maybe that he’s become too American? 'Cause I’ve not known the Brits to use “butt” all that much.
Maybe it’s the opposite of not being arsed? or the sensation you get when you pull your finger out?
You’re mishearing him. He’s saying “Your butt in bitchin’, man!”
It’s a pass, silly!
My apologies. It is “Your ass is itching.” I didn’t mean to include the word “mean” in the quotes. Also, this being GQ I did not wish to use Ass in the tittle and I did not think that substituting butt would change it much.
Itching: “To have a persistent, restless craving” (American Heritage)
Your ass is itching to tell the boss. -> You are eager to tell the boss.
Not sure which is a funnier phrase, “Your ass is itching mean” or “Ass in the tittle”.
I think I’ll just have to start using both of them around the office.
In my family, the following two phrases:
“Ah, your ass is itchy”
“Your ass is suckin’ blueberries” (Thup, Thup, Thup sound effect optional)
are both used to indicate that the person is attempting to BS you.
From the context he uses it, I believe he means it as your family does. Any idea of the origin? Are you a brit by the way, or is this also common in the US?
No idea of the origin, I think it’s just giving back irrelevent nonsense to someone you believe to be feeding you the same.
I’m in the US, no British influence on my family that I’m aware of.
You, sir (or ma’am), have a strange family.