RUST

Oxidised iron (4)

Solution has appeared in 3 crosswords (3 across and 0 down):

• Quick crossword No 15,919 — 2021-05-14 23:00:10
  11A: Deteriorate through corrosion (4)
• Quick crossword No 15,653 — 2020-07-07 23:00:01
  8A: Reddish-brown colour (4)
• Quick crossword No 15,216 — 2019-02-13 00:00:05
  20A: Oxidised iron (4)