Source of some nondairy milk (3)

I believe the answer is:

oat

(Other definitions for oat that I've seen before include "Basis of porridge" , "Cereal (singular)" , "Cereal grass" , "Cereal plant" , "Food grain" .)

I've seen this clue in 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.