flag carrier
noun1
A person carrying a standard or flag, usually at sporting events and parades, previously on the battlefield.
2
Government, Politics 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
Business A transportation company, such as a shipping or airline company, that is registered in a given state.
4
Aeronautics, Aerospace, Aviation, Business, Engineering, Natural sciences, Physical sciences 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.2021 June 30, Philip Haigh, “Regional trains squeezed as ECML congestion heads north”, in RAIL, number 934, page 52: