infantry

n. (Military) ground troops, soldiers who fight on foot; branch of the military made up of foot soldiers

For the computer game, see Infantry (computer game). Infantry or footmen are soldiers who fight primarily on foot with small arms in organized military units, though they may be transported to the battlefield by horses, ships, automobiles, skis, bicycles, or other means. The word comes from the same Latin root as 'infant', either via Italian, where it referred to young men who accompanied knights on foot, or via Spanish, where the infantes (royal princes who were not heirs to the throne) commanded the footmen, hence known as infanteria.
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Noun
1. an army unit consisting of soldiers who fight on foot; "there came ten thousand horsemen and as many fully-armed foot"
(synonym) foot
(hypernym) army unit
(hyponym) paratroops
(classification) military, armed forces, armed services, military machine, war machine

(n.)
A body of soldiers serving on foot; foot soldiers, in distinction from cavalry.
  

(n.)
A body of children.
  

A dismounted fighting man. During the bulk of the Middle Ages, the role of infantry was considered to be the role of the common man, a distinction is retains to a degree even in modern warfare. Generally, medieval infantry was more lightly armoured than the heavy cavalry that formed the heart of a medieval army. During the 14th century, the English experimented with the use of infantry and artillery to great effect, defeating the cavalry-heavy armies of France and Spain and the massed spearmen of the Scots. Gradually, knights began to fight on foot as often as they fought mounted, but by this time the use of gunpowder changed the role of the knight and gave him the tactical role of officer rather than cavalryman.