What is the origin of term bye in football?

Answer 1

In a sports context, it comes from cricket, where a bye is a type of play where the batsman can advance and score without ever hitting the ball. (I really don't know anything about cricket, so I'm not sure how that works.) The same meaning was applied to other sports where teams advance to a later round without playing. You can see that in the NFL during the playoffs, where the top two seeds advance to the second round without playing in the first round. The meaning was then further extended to signify simply getting a week off, effectively "skipping" that week without playing and starting up again the following week.

The word itself comes from the word "by" when it's used in the sense of something secondary, as in a "bypass." So when you have a bye, you bypass playing that week.