Coming from the universe of Battletech and MechWarrior, "Aff" is an abbreviation of "Affirmative," meaning "yes." Its opposite, naturally, is "Neg," short for negative.

When expecting an answer one way or another, the prefix "qui" may be added.
Gunter: "Enemy Kodiak at 2 o'clock. Should I open fire, quiaff?"
Von Helsing: "Aff. Take out his legs."
by Benny the Icepick August 31, 2007
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Someone or something that is typically african and can seem bush.
Debbie: I didn't off the light.
Vicky: lol. You're so aff!
by Vicky A March 16, 2008
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an expression of dissapointment or supurprise,with out saying fuck. in attempt to be civil.
AFFF! Theres a cop behind you.
or
AFFF! I can't find my keys...
by jmb February 25, 2005
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Cool person named aff it’s me guys I’m aff im so cool omg
by Afari ferrari February 8, 2022
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AFF: abbreviation for "Away for Flow", which indicates that the person is being in the zone, thus, shouldn't be disturbed (hence the "away").

In this era of remote working where a coworker does not necessarily know the physical state of another coworker, this abbreviation can be used to politely hang/reject a conversation (or chat) when the person is being focused (i.e "AFF, will reply later").

About flow: "flow, also known colloquially as being in the zone, is the mental state of operation in which a person performing an activity is fully immersed in a feeling of energized focus, full involvement, and enjoyment in the process of the activity." (Wikipedia, at en.wikipedia.org/wiki/Flow_(psychology))
Example 1
A: "Can you go get some documents outside?"
B: "Sorry, AFF. Will do it later"

Example 2
A: "Yo guys, I'll be going AFF. Will be back after lunch"
by mosshead July 22, 2018
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A Noun Discriminating Against African People
by Mix-Race Man On Road February 24, 2017
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