Wordnet 3.0
NOUN (2)
1.
the chief one of a related group;
- Example: "it is their flagship newspaper"2.
the ship that carries the commander of a fleet and flies his flag;
The Collaborative International Dictionary of English v.0.48:
Flagship \Flag"ship`\, n. (Naut.)
The vessel which carries the commanding officer of a fleet or
squadron and flies his distinctive flag or pennant.
[1913 Webster]
WordNet (r) 3.0 (2006):
flagship
n 1: the chief one of a related group; "it is their flagship
newspaper"
2: the ship that carries the commander of a fleet and flies his
flag