A person who always calls back immediately after a telephone call with them has ended. Usually done to pronounce a final, dramatic closing statement to the previous conversation, although occasionally merely to add information which had been overlooked previously.
So after she hung up on me, the two-caller was right back on my ass screaming "I hate you!" into the phone!

Sorry to two-call, but I gave you the wrong address a minute ago.
by CheapYuppie December 6, 2007
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