GUANO

Seabird excrement, once prized as fertiliser (5)

Solution has appeared in 2 crosswords (0 across and 2 down):

• Quick crossword No 16,488 — 2023-03-11 00:00:04
  3D: Seabird and bat excrement once widely used as a fertiliser (5)
• Quick crossword No 15,231 — 2019-03-02 00:00:19
  18D: Seabird excrement, once prized as fertiliser (5)