The “time” invested in developing the pieces harmoniously. A pawn is said to be worth 3 tempi, or 3 turns.

A unit of time represented by a move. For example, forcing the opponent to move a piece twice in the opening can gain a tempo. Plural is "tempi".

A unit of time considered as one move. A player may gain a tempo in the opening when the opponent moves the same piece twice. In the endgame, one may wish to lose a tempo by triangulation in order to gain the opposition. Plural: tempos or tempi.