A deceptive play attempting to score a trick with an unsupported honour.
Suppose you are South on Layout 1. If you judge that West holds the king, you might lead the queen (as you would if you held the jack with it) hoping to escape a cover. If the position were actually as in Layout 2, West would be right not to cover since you could take the king with the ace and finesse the nine on the second round to score three tricks.
The Chinese finesse has a chance of success only if West has the king but neither the jack nor the ten, so it is usually not the best line of play.