noun
dregs
DREGZ/dreɡz/
The least desirable remains of something.
Dark wine and coarse sediment form the dregs at the bottom of the glass.

Etymology
Dregs originally named the sediment that settles at the bottom of a liquid. That leftover material became an image for the worthless residue or least desirable part of anything.
In context
the guides are both elementals and elementaries, and not even a decent half and half, but the very dregs in the mug of the mediumistic beer.
More examples
- We sort through the dregs of the clearance bin.
- Nobody wants the dregs left on the snack tray.
- The sequel recycles the dregs of the writer's old ideas.
Forms
dregs