Constitution-class Starship
A Constitution-class starship is also known as Starship-class. They were designed for long duration missions with minimal outside support.
The Jefferies design first seen abroad the NX-class starships, and the dual-nacelle design first employed by Cochrane’s Phoenix, had become standard for Federation starships. To be precise, the Constitution-class starships are descendants of the NX-class starships.
The Constitution-class lineage was launched some time prior to 2245, and served as Federation-Starfleet front-line vessels for much of the 23rd century.
In 2267 there were around twelve Constitution-class starships in the fleet (“Tomorrow is yesterday, TOS”).
The ships were probably decommissioned at the end of the 23rd century (non-canon).
It is probably safe to assume that the USS Enterprise (NCC-1701) was the first Federation-Starfleet ship to bear the name Enterprise.