FREEFALL

Rapid decline (4,4)

Solution has appeared in 2 crosswords (1 across and 1 down):

• Quick crossword No 16,075 — 2021-11-13 00:00:16
  16A: Unstoppable rapid decline (4,4)
• Quick crossword No 15,923 — 2021-05-19 23:00:21
  11D: Rapid decline (4,4)