Dreadnought

The Dreadnaught was a type of Cardassian interstellar cruise missile. They used them to attack Maquis worlds. One was captured and refitted by Belanna Torres. We see her thought process at work with this device. She stuffed the missile with as much advanced technology the Maquis could get, and planned to blow it up.

Since the vehicle had no crew, it wasn't technically a starship. It may have been used by the Cardassians to attack Maquis targets in the DMZ without openly violating their treaty commitments.