Is there one?
A remix uses the original tracks from the song but re-arranges them and possibly adds new sounds to them.
A cover is when an artist performs an existing song that was created and/or performed by another; this may also include some new arrangements or auditory additions.
Though this is distinct from sampling. A remix (heavily) uses samples from the original song, but just because it uses a part of the original track doesn’t make the song a remix in and of itself.
Remix: “Tom’s Diner” by D’n’A, which used the original vocals by Suzanne Vega and added a House beat
Cover: “Pinball Wizard” by Elton John, using Pete Townshend’s lyrics and melody but no master tracks from the Who’s original version.
Sample: “Ice Ice Baby” by Vanilla Ice, which used snippets of David Bowie/Queen’s “Under Pressure” for a distinctly different song.
According to him at the time it wasn’t even the same sample! I remember watching that when it first aired on MTV News and laughing hysterically at his ridiculous claim.
To his credit he did issue a mea culpa some 20 years later…
In that “apology” video he doesn’t say anything about sampling any other song… just that he’s “Sorry for the hairdos, the baggy pants, the scandals, the lies, the gangs, and I’m sorry about the music”. Whatever that means… I’m pretty sure the video is meant as a joke.