gravitational wave

noun2

1. •
   A fluctuation in spacetime caused by accelerating mass, which propagates as a wave at the speed of light.

   • It is therefore apparent that the existence of gravitational waves can be deduced from general relativity just as the existence of electromagnetic waves can be deduced from Maxwell's theory. — 1941
2. •
   (nonstandard, old-fashioned) A gravity wave.

   • In the used model sound waves and external gravitational waves have been filtered; combined inertial-internal gravitational waves, however, are still included in the equations. — 1959