/ ˈliːdə(r); NAmE / noun
1.
a person who leads a group of people, especially the head of a country, an organization, etc. :
a political / spiritual, etc. leader
the leader of the party
union leaders
He was not a natural leader .
She's a born leader .
2.
a person or thing that is the best, or in first place in a race, business, etc. :
She was among the leaders of the race from the start.
The company is a world leader in electrical goods.
—see also market leader
3.
( BrE ) (also con·cert·master NAmE , BrE ) the most important violin player in an orchestra
4.
( BrE ) = editorial