A no-ship was a starship, and type of no-chamber, that was invisible to prescience. This meant that its movements or occupants could not be seen by many of those who possessed prescient powers, such as Guild Navigators, and some Atreides descendants.
No-ships came into heavy use during and after the time of The Scattering. They were used by people fleeing the Old Imperium into the vast unknown of uncharted space. Since no-ships possessed advanced calculation systems, they did not require a Guild Navigator's prescient abilities to avoid collision with interstellar bodies. Because of this, they could escape charted territories without difficulty. However, this also meant that they came dangerously close, if not outwardly defied, the prohibition of the use of computers.
During the time of the Honored Matres, when the Lost Ones were returning to the Old Imperium, no-ships had become commonplace. Not only were they used to hide individuals and their movements, but they were also employed as planetary defenses by being placed in orbit. In this way, those who attempted to search for individuals with prescience would find it difficult, if not impossible to detect them.
At times, no-ships were often armed and took part in space battles.
Like a no-chamber, anything inside a no-ship was hidden from prescient vision and other methods of detection, although when in standby mode, it was visible with the naked eye. A no-ship had much greater technological capability than a no-chamber; for example, it was able to perform the functions of a Guild Navigator. Specifically, a no-ship's computer was capable of enough limited prescience that it could successfully navigate its way through a fold in the fabric of the space-time continuum.
Evidence suggested that certain individuals with Atreides ancestry were capable of using their prescient powers to "see" no-ships. Miles Teg, a Bashar during the arrival of the Honored Matres, and a descendant of Ghanima Atreides and Farad'n Corrino, was cloned by the Bene Gesserit, and his clone imprinted with the ability to nullify no-field invisibility after being exposed to a device called a T-Probe, an offshoot of an Ixian device.
No-ships were gigantic. Individuals were capable of living within one for years without suffering many of the undue effects one would associate with such confinement, implying a very large and luxurious living space. More strikingly, a no-ship was capable of transporting an adult sandworm, with enough sand for it to survive for the duration of the prolonged trip.
No-ships represented the fading of both the restrictions on thinking machines and the power of the Spacing Guild, whose navigators were previously the only beings capable of interstellar navigation in their heighliner spacecraft.