One who incessantly uses the text feature on a cell phone to send text messages to an individual or a group advising the recipient(s) of their most mundane accomplishments.
Dude, Maggie the "serial texter" just sent me a message that she got her haircut; what's next, a text that she just dropped a deuce ?
A person you hate intensely not because they deserve such hatred but because they serve as a focus for your general hatred. A healthy way to dispense with excess animosity.
Jake's not really that big an asshole. He just serves as my hate sink.