wingback

Short definition from Wiktionary

Noun

1. 1
   A player who doubles on either side of the center as a defender when their team is defending, and a winger when they are attacking.
2. 2
   A running back who is in formation near the line of scrimmage and outside the tackles, a slotback.
3. 3
   One of the projecting side pieces on a wingback chair.
4. 4
   A wingback chair.