Cubit (kūb&ibreve_;t), n. [L. cubitum, cubitus; elbow, ell, cubit, fr. (because the elbow serves for leaning upon) cubare to lie down, recline; cf. Gr. kybiton elbow, kyptein to bend, stoop, kyfos bent, stooping, humpbacked. Cf. Incumbent, Covey.] 1. (Anat.) The forearm; the ulna, a bone of the arm extending from elbow to wrist. [Obs.]
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2. A measure of length, being the distance from the elbow to the extremity of the middle finger.
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&hand_; The cubit varies in length in different countries, the Roman cubit being 17.47 inches, the Greek 18.20, the Hebrew somewhat longer, and the English 18 inches.
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