Castling

Castling was a chess move.

In the "chess match" between the Seventh Doctor and the Cybermen, when the Cyber-Leader moved his pawn to discover check, Ace replied by neatly castling with the bow of Nemesis. (TV: Silver Nemesis)

Behind the scenes
The nature of the move is not elaborated upon in Silver Nemesis. It involves the king and one of the rooks.