major (adj)

Exports play a major role in key sub-sectors.
Our prices are lower on 2,000 items than those of all our major competitors.
Some major international companies refused to do business with them.
The company announced a major restructuring of its operations.
His promotion to a major role in the project marked a significant achievement.
The team faced a major challenge but remained determined.
The storm caused major disruptions to transportation services.
Implementing a major policy change requires careful consideration and planning.