UNHEARDOF

Without precedent (7,2)

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

• Quick crossword No 16,672 — 2023-10-11 23:00:52
  7D: Previously unknown (7-2)
• Quick crossword No 16,190 — 2022-03-28 23:00:06
  6D: Without precedent (7,2)