What does ATT mean in football?

Answer 1

'att' stands for 'attempts'. You might see this in a stats line for a quarterback, which would mean pass attempts, or in a stats line for a placekicker, which would mean field goal attempts or point after touchdown attempts.

attempt for what

Answer 2

It means "attempts." A lot of NFL stats are percentages. You divide the number of times the player or team completed the task in question - passes, sacks, whatever - into the number of times they attempted to do it.