Moleculon nanoscaler
From Tardis Wiki, the free Doctor Who reference
Molecular nanoscalers miniaturised matter. They were used for shrinking down surgeons to enter the patient. The nanoscaler on the Aristotle was used to shrink down the Twelfth Doctor, Clara Oswald, Journey Blue, Gretchen, and Ross to enter "Rusty", a malfunctioning Dalek. (TV: Into the Dalek)