[n] the head and sharpened point of a spear
[n] the leading military unit in an attack
[n] someone who leads or initiates an activity (attack or campaign etc.)
[v] be the leader of; "She spearheded the effort to find a cure for the disease"
force, head, lance, lead, leader, military force, military group, military unit, pike, point, shaft, spear
\Spear"head`\, n. The pointed head, or end, of a spear.