flagship

noun

1. The ship occupied by the fleet's commander (usually an admiral); it denotes this by flying his flag.

   “After Russia’s flagship in the Black Sea, the Moskva, sank last week, the authorities said that the entire crew of more than 500 had been rescued.”

2. The ship regarded as most important out of a group, e.g. a nation's navy or company's fleet.
3. (attributive, broadly, often)The most important one out of a related group.

   “The retail company's store in London is their flagship.”

   “Ars Technica’s Ron Amadeo considered the two smartphones together, and claimed them worthy flagships for Android: […]”

   “Next year, Stella McCartney’s London flagship store will move from Bruton Street to a landmark Old Bond Street location. The move is the most prominent symbol of the label’s strong financial results.”

   “Transport Minister Baroness Vere has conceded that the Government does not yet know how its flagship £96 billion Integrated Rail Plan "will actually work on the ground".”

   “The latest prime minister, the recently reappointed Sébastien Lecornu, may have bought himself a stay of execution on Tuesday, sacrificing Emmanuel Macron’s flagship pensions overhaul in exchange for opposition Socialist votes as the price for his government’s survival.”

verb

1. (transitive)To act as a flagship for.