To act as a flagship for.
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 give a preface to.
To introduce or make a comment before (the main point).
An introduction, or series of preliminary remarks.
A title or epithet.
The beginning or introductory portion that comes before the main text of a document or book.
The prelude or introduction to the canon of the Mass.