Emily Dickinson Lexicon

CU'BIT, n. [L. cubitus, the elbow; Gr. κυβιτον; probably allied to L. cubo, and signifying a turn or corner.]

1. In anatomy, the fore arm; the ulna, a bone of the arm from the elbow to the wrist. – Coxe. Encyc.
2. In mensuration, the length of a man's arm from the elbow to the extremity of the middle finger. The cubit among the ancients was of a different length among different nations. Dr. Arbuthnot states the Roman cubit at seventeen inches and four tenths; the cubit of the Scriptures at a little less than 22 inches; and the English cubit at 18 inches. – Encyc.