Gladstone bag
From Tardis Wiki, the free Doctor Who reference
Gladstone bags were a type of stiff leather bag carried by physicians.
Doctor Lauren Anderson owned a Gladstone bag, which she used to smuggle all the doses of Cyberon drug out of St John's Hospital without Tom Mordley knowing after she realised the substance was dangerous. (PROSE: Cyberon)
The Doctor carried a a bigger-on-the-inside Gladstone bag from their first (COMIC: Shark Bait) to their eighth incarnations, using it to transport various useful gizmos. (TV: Doctor Who)