Previously a letter, now turned into a word to representanger, hate and annoyance. It is also a signal to removes oneself from the presence of the person saying it. Often also used as a signal to shut another person up.
A - "Come over, I miss you"
B - "I can't, I'm too fat."
B - " *far. Damn autocorrect. "
A - "You should use that gym membership I got you."