Rump-sprung Edit Meaning

1.

Of or pertaing to the condition of a seat or sofa upon which a large person has spent a lot of time. Worn through uphostry and collapsed springs. Typically form fitting to a specific ass.

I can't sit on the near end of the sofa, its rump-sprng to aunt Ethel's ass.

It's a good truck but that drivers seat is rump-sprung.