An influential person is someone who has a great deal of power and influence in their field. A LUMINARY is a person who is renowned for their achievements, a NABOB is a wealthy and powerful person, a MOGUL is a powerful businessperson, a MOVER is someone who is active in making things happen, a MAGNATE is a powerful and influential businessperson, a TITAN is a powerful and influential figure, a fatcat is a wealthy and influential person, and an elderstatesman is an experienced and respected leader.