Definitions:
the person who leads or commands a group, organization, or country

the principal player in a music group.

a leading article in a newspaper.

a short strip of non-functioning material at each end of a reel of film or recording tape for connection to the spool.

a shoot of a plant at the apex of a stem or main branch.

a series of dots or dashes across the page to guide the eye, especially in tabulated material.