Longman Dictionary of Contemporary English
ground forces
noun
EXAMPLES FROM CORPUS
▪ A security fence, with watchtowers, protects the base against attack by ground forces.
▪ Army commander Gen. Dogan Gures was appointed ground forces commander from Aug. 30, 1989.
▪ In addition to the cuts in its ground forces, some military orders have had to be postponed.
▪ The remainder hid out, waiting for the arrival of allied ground forces.
▪ These were understood to stop short of deployment of major ground forces.
Wiktionary
ground forces
n. (context military English) all military units operating on the ground, including tanks, soldiers, artillery e.t.c.
WordNet
ground forces
n. a permanent organization of the military land forces of a nation or state [syn: army, regular army]