Describing an individual whom is rendered virtually, yet not literally, deaf due to their playing of their MP3 device (most specifically an iPod) at a volume so loud that it creates a situation in which others cannot communicate with them verbally.
"What an asshole! I tried to get his attention by yelling into his ear and he didn't even pay any mind to me!"
"Dude, don't sweat it. He had his earbuds in and hence was most likely iDeaf."