The most important one out of a related group.
The ship occupied by the fleet's commander (usually an admiral); it denotes this by flying his flag.
The ship regarded as most important out of a group, e.g. a nation's navy or company's fleet.
To act as a flagship for.
A notable or eminent person or thing.
The quality or state of being notable or eminent.
Locally eminent people; the bourgeoisie or upper middle class