look up any word, like ratchet:
Chronic joint pain in the dominant texting digit from repetitive typing on iPhone and other PDAs.
The cold weather is aggravating the iThritis in my right thumb. I can't answer another text today!
by St. Johns Belle February 04, 2012
Thumb pain or cramping due to too much typing on a cell phone, particularly on an i-device.
Tweeters should limit their hashtag use, lest their iThritis flare up and make them put their phones down.
by Ctrl_T February 26, 2013