Exchange sacrifice
From Conservapedia
An exchange sacrifice in chess is when a player intentionally trades a superior piece for an inferior one in a capture and recapture of pieces, in order to gain an advantage in position on the board.
In Fischer-Spassky Game 6 of their world championship in 1972, Bobby Fischer did an exchange of pieces that sacrificed value but gained strength in position, enabling him to approach checkmate and thereby compel Boris Spassky to resign.
