Paints on palettes (4)

I believe the answer is:

oils

(Other definitions for oils that I've seen before include "Viscous substances kept in silo" , "Well-produced" , "paintings?" , "Soil, oddly, used by painters" , "Liquids for frying" .)

I've seen this clue in the LA Times and The Wall Street Journal.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.