noun / verb
duel
DOO-uhl/ˈduːəl/
A fight or contest between two opponents.
The two swordsmen duel while their seconds watch from a distance.

Etymology
Latin duellum meant 'war.' Its narrower meaning of one-on-one combat apparently arose through a fancied connection with duo, 'two,' eventually yielding the formal, prearranged fight.
In context
the smallsword, a fashionable weapon often used in a duel to settle disputes.