Jack (card)
A jack or knave was a playing card featuring a man in the traditional or historic aristocratic or courtier dress.

Two artificial knaves who appeared as knights, characters from Alice Through the Looking Glass, were alongside the Queen of Hearts as they chased the landing party from the  during its second visit to the Shore Leave Planet in 2269. ()

As Worf was preoccupied with his loss to Counselor Deanna Troi in a poker game, he told Geordi La Forge that he had jacks and eights, she bluffed him with a pair of sixes. ()

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