[noun] [U], [adjective] [not gradable] [specialized] - (in the game of chess) (on) the side of the board on which your queen is positioned at the start of the gameI very rarely castle on the queenside.McDonald built up a strong queenside attack/defence.
QUEENSIDE
Meaning of QUEENSIDE in English
Cambridge English vocab. Кембриджский английский словарь. 2012