What does "flag carrier" mean?

A person carrying a standard or flag, usually at sporting events and parades, previously on the battlefield.

What is a synonym for "flag carrier"?

Common synonyms include: emirates, swissair.

noun

noun ·Rare ·Advanced level

Noun

1
A person carrying a standard or flag, usually at sporting events and parades, previously on the battlefield.
2
A strong supporter of a cause, or perhaps the strongest and most visible supporter of said cause.
"Bill was the flag carrier of the movement to improve inner city education."
3
A transportation company, such as a shipping or airline company, that is registered in a given state.
4
A national airline (typically having the flag, or other national insignia, on the tail).
"I'll be interested to see how this service does. It will be basic with fares to match, so will be akin to a budget airline taking on a flag-carrier."
5
An aircraft carrier serving as a flagship.

"Bill was the flag carrier of the movement to improve inner city education."