be first in line

1 ) to be likely to receive something
Rachel was reported to be in line for the job of team manager.
be first/second/next in line: He is next in line for promotion
2 ) be in line for something/be in line to do something
to be very likely to get or be given something
I should be in line for promotion soon.
first/second/next etc in line for
He must be first in line for the editor’s
3 ) be first/second/next etc in line to the throne
to be the person who has a right to become a future king or queen
As the eldest son, he was next in line to the throne