From WordNet (r) 2.0 (August 2003) [wn]:
handball
n 1: a small rubber ball used in the game of handball
2: a game played in a walled court or against a single wall by
two or four players who strike a rubber ball with their
hands
From The Collaborative International Dictionary of English v.0.48 [gcide]:
Handball \Hand"ball`\ (h[a^]nd"b[add]l`), n.
1. A small ball, usually made of rubber, thrown or struck
with the hand in various games.
[Webster 1913 Suppl.]
2. A game played with such a ball, as by players striking it
to and fro between them with the hands, or, when played in
a walled court or against a single wall, striking it in
turns against a wall, until one side or the other fails to
return the ball.
[Webster 1913 Suppl.]