A starship that fights at Narendra III in 2344.
The USS Enterprise-C was an Ambassador-class starship commanded by Captain Rachel Garrett. In 2344 it answered a distress call from the Klingon outpost at Narendra III, which was under Romulan attack, and the ship was badly damaged in the fight.
In the Next Generation episode Yesterday's Enterprise, the ship passes through a temporal rift and emerges in 2366. Its disappearance from the battle has changed history, and the Federation is losing a long war with the Klingons. Guinan senses that this timeline is wrong and urges Picard to send the Enterprise-C back.
Garrett is killed during a Klingon attack, and Lieutenant Richard Castillo takes command. Lieutenant Tasha Yar, who in this timeline is still alive, volunteers to go with them. The Enterprise-C returns to Narendra III and is destroyed defending the outpost, and its sacrifice impresses the Klingons enough to help bring about lasting peace with the Federation.