What appears as movement to observer is apparent motion. Any apparent motion is with reference to a moving frame. Absolute frame for absolute motion in astronomy is still a mirage.
As an observer we see Moon other planets our star Sun and other stars moving at different speeds. This is apparent motion. The frame of reference is a frame at your position with directions that appear to be fixed in your view. This is observer-centric apparent motion. Likewise there are Earth-centric Sun-centric Milky Way-centric … apparent motions.
The fitting of absolute frame of reference for absolute motion for continuous marking of of the space vacated by everything (relatively) at any instant is still at large. .