Sapper n. : One who saps; specifically (Mil.), one who is employed in working at saps, building and repairing fortifications, and the like.

Example:
How does someone become a Sapper?

Taxonomy
Sapper, combat engineer, tasks, Sapper Leader Course, soldiers, army, Sappers and Miners, engineer, PAVN, Sapper Tab, US Army, enemies, Viet Cong, saps, Marine, free encyclopedia, sapeurs, the enemy.

Defination from the web:
sapper or combat engineer is an individual soldier who performs a variety of combat engineering duties. ... A modern sapper's tasks involve facilitating movement and logistics of allied forces and impeding ... Sapper (abbreviated Spr) is the Royal Engineers' equivalent of Private. ...