WHIG

Historical predecessor of Liberal (4)

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

• Quick crossword No 16,170 — 2022-03-05 00:00:08
  21D: Old politician opposed to the Tories (4)
• Quick crossword No 15,691 — 2020-08-20 23:00:33
  3D: Historical predecessor of Liberal (4)