To 'spearhead' something is to lead a group in an attack or in a strategic movement or to direct a group of people in some way. You could 'spearhead' an organisation by being responsible for major decisions or 'spearhead' a political movement by beginning it or leading others. This verb can be used in social and professional contexts.

1. The air force spearheaded the government's attack on the rebel positions, destroying targets and making the situation less dangerous for the ground troops that followed.
2. A vigilante organisation spearheaded a cyber attack on the government website.

1. Helen was spearheading the drive for better working conditions in the factory. For that reason, the boss had a particular dislike for her.
2. As the most qualified and experienced member of the team; Kevin was chosen to spearhead the company's new marketing campaign.