means A team sport in which two sides, separated by a high net, use their hands and arms to bat a ball back and forth, trying to ground it on the opponent's court.

from A transparent compound of "volley" plus "ball." The "volley" part traces back through French "volée," meaning a flight or flying, from Latin "volare," to fly — the same root that gives us "volatile." So a "volley" was originally a thing struck or fired in mid-flight, whether arrows, gunfire, or a ball that hasn't yet touched the ground. The sport itself is an American invention of the late 19th century, first dubbed "mintonette" before someone sensibly noticed the players were volleying a ball and renamed it accordingly.