The acronym stands for 'as fuck.'

1. (common) Stands for "as fuck".
2. (photographic) Short for autofocus. Sometimes combined with other letters, e.g. when talking about camera-side, AF-S is single autofocus (only done the moment you tell it to) and AF-C is continuous autofocus (done constantly between turning it on and off).

Means 'as fuck' and is used to clarify things. You can also use it as the word 'very' or 'really'. Mostly used online or in text messages.

"As foretold." To such a degree it was foreseen in prophesy.

We already had OMG, LOL, and WTF, but 2014 brought about a new acronym that was popularized thanks to texting and online chatting. Abbreviating "as fuck" as AF has been happening for a while, but it was never actually spoken aloud as much as 2014. Some pronounce it "A Eff" and others simply "af."