Jack (jăk), n. [Pg. jaca, Malayalam, tsjaka.] (Bot.) A large tree, the Artocarpus integrifolia, common in the East Indies, closely allied to the breadfruit, from which it differs in having its leaves entire. The fruit is of great size, weighing from thirty to forty pounds, and through its soft fibrous matter are scattered the seeds, which are roasted and eaten. The wood is of a yellow color, fine grain, and rather heavy, and is much used in cabinetwork. It is also used for dyeing a brilliant yellow. [Written also jak.]
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Jack (?), n. [F. jaque, jacque, perh. from the proper name Jacques. Cf. Jacquerie.] A coarse and cheap mediæval coat of defense, esp. one made of leather.
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Their horsemen are with jacks for most part clad. Sir J. Harrington.
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Jack, v. i. To hunt game at night by means of a jack. See 2d Jack, n., 4, n.
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