TANK

Water reservoir (4)

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

• Quick crossword No 15,938 — 2021-06-06 23:00:51
  25A: Armoured fighting vehicle on caterpillar tracks (4)
• Quick crossword No 15,416 — 2019-10-03 23:00:59
  2D: Water reservoir (4)