n. 肘尺

[ noun ]
an ancient unit of length based on the length of the forearm
<noun.quantity>

Cubit \Cu"bit\ (k[=u]"b[i^]t), n. [L. cubitum, cubitus; elbow,
ell, cubit, fr. (because the elbow serves for leaning upon)
cubare to lie down, recline; cf. Gr. ky`biton elbow, ky`ptein
to bend, stoop, kyfo`s bent, stooping, humpbacked. Cf.
{Incumbent}, {Covey}.]
1. (Anat.) The forearm; the ulna, a bone of the arm extending
from elbow to wrist. [Obs.]

2. A measure of length, being the distance from the elbow to
the extremity of the middle finger.

Note: 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.