Tovarishch

Tovarishch was a Russian word meaning comrade, friend, or ally. After possessing Captain Sorin in 1943, Fenric called Ace tovarishch to trick her into revealing how to beat the Seventh Doctor's chess puzzle. (TV: The Curse of Fenric)

Felnikov later called Ace tovarishch when they met again in 1989, after first meeting in 1967. (AUDIO: Crime of the Century)