grounder(n = noun.act) ground ball, groundball, hopper - (baseball) a hit that travels along the ground;
is a kind of hit, hitting, striking
has particulars: chop, chopper, roller
Derived form verb ground₈

   A batted ball that hits the ground before it leaves the infield, or the act of hitting a baseball along the ground; also called ground ball; -- contrasted with fly or fly ball. [WordNet 1.5]