So gravity waves are just what laypeople call waves...

what crappy naming! the essential mechanism is fluid-dynamics not gravity...how confusing

Name seems fine to me.

From the first paragraph of the wiki-page:

In fluid dynamics, gravity waves are waves generated in a fluid medium or at the interface between two media when the force of gravity or buoyancy tries to restore equilibrium. An example of such an interface is that between the atmosphere and the ocean, which gives rise to wind waves.

but the same waves could be reproduced without gravity in an appropriate accelerating frame (e.g. in a rotating body at a Lagrange point) so gravity isn't _essential_, whereas it is for gravitational waves

Gravity is the result of an appropriately accelerating frame (i.e. the curvature of spacetime).

Thanks.