Fertiliser from the waste of seabirds (5)

I believe the answer is:

guano

(Other definitions for guano that I've seen before include "Fertiliser from seabirds" , "Fertiliser (either from bird droppings or artificial)" , "mess about by the sea" , "Seabird excrement, once prized as fertiliser" , "Fertilizer from the waste of seabirds" .)

I've seen this clue in The Guardian.

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.