Called aggaka in the language Coraabish.
Agrava is a general term referring to smaller, interplanetary ships used for personnel or cargo transportation. Agravas do not meet physical norms for oscillating via strings. As such, they mostly rely on their bi-ion engines to help them cover the long distances between individual planets in a single star system. Agravas are often used for personnel transport from the strings to their nearby inhabited worlds.
Agravas are used by governments as well as private subjects. Their high purchase price is justified by their perfect flight dispositions and often comfortable interior. The main advantage of agravas is their characteristically high maximum velocities.
Larger transplanetary vehicles are called magravs.