Ginkgo gunk (3)

I believe the answer is:

sap

(Other definitions for sap that I've seen before include "Internal tree moisture" , "Tree's blood" , "Plant juice; undermine" , "Fluid in plant stems" , "Vigour, energy" .)

I've seen this clue in The Washington Post.

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.