Piqué tour is a classical ballet term meaning “pricked turn” It is most commonly used as simply “pique turn” which is a very common step for female ballet dancers.
A dancer doing a piqué tour, or piqué turn, will step directly on to a full point (when in pointe shoes) or a high demi-pointe right as they begin the turn onto that same leg. A piqué turn can be done with the working leg in passe (both front and back), in arabesque, attitude or any other position that may be given. The freedom for the position is open because piqué turn simply describes that the dancer has gone into the turn with a pique as opposed to relevé.
Pique turns, or tours, can be done both en dedans or en dehors, but the most common in ballet class or in choreography are en dedans.