libero

noun

li·​be·​ro li-ˈber-(ˌ)ō  ˈli-bə-(ˌ)rō 

plural liberos

1

: a volleyball player who serves as a defensive specialist, is always positioned on the back line, and is allowed an unlimited number of substitutions

Distinguished from his or her teammates by a different colored jersey … , the libero may come into the game for any other player any number of times …

—Kelley King

2

: a soccer sweeper

The sweeper, or libero position, was created by the Italians as strictly a defensive position, but Beckenbauer converted it into a strong offensive weapon …

—Alex Yannis

Word History

Etymology

borrowed from Italian, "sweeper (in soccer)," short for battitore libero, literally, "free hitter"; libero "free," going back to Latin līber — more at liberal entry 1

Note: The player designated libero was probably so called because he was not given the assignment of marking a particular opposing player.

First Known Use

1967, in the meaning defined at sense 2