Homburg hat
From Tardis Wiki, the free Doctor Who reference
Homburg hats were headwear from Germany.
While in India, the Eighth Doctor wore a grey homburg cap. (PROSE: The Eye of the Tyger)
While investigating the apparent conspiracy against Winston Churchill in 1936, the Sixth Doctor wore a grey Homburg hat with a black band. (PROSE: Players)
Arnold Farrow wore a black Homburg hat. (PROSE: Planet of Giants)