Spearhead (noun)

1. The pointed head of a spear.
2. A person or group that leads or initiates an action or movement.

Origin:

Old english sperehed, from the base of spear + head. the verb spearhead (mid 19th century) originally meant "provide with a spearhead"; its current sense dates from the early 20th century.

Examples:

1. The spearhead of the spear had been broken off.
2. He was chosen to spearhead the campaign for the new project.
3. The company has appointed a new executive to spearhead its growth strategy.
4. The team's captain was the spearhead of their offense.
5. The spearhead of the spear was made of sharpened metal.