The term "gravity wave" refers to waves typically on the ocean or in weather systems where the restoring force is gravity (as opposed for example to capillary waves where it is surface tension). Those related to GR are called "gravitational waves". Unfortunately, the Oxford English dictionary has picked up on the phrase "If the distance changes, you've detected a gravity wave." from this publication and used it as an example to claim that "gravity wave is another name for gravitational waves".