The word for today is…
cubit (noun) – An ancient unit of linear measure, originally equal to the length of the forearm from the tip of the middle finger to the elbow, or about 17 to 22 inches (43 to 56 centimetres).
Source : The Free Dictionary
Etymology : The cubit is an ancient unit of length that may have originated in Egypt close to 5,000 years ago. Cubit can refer to various units used in the ancient world, the actual length of which varied from time to time and place to place, but which was generally equivalent to the length of the human arm from elbow to fingertip—roughly about a foot and a half. (Appropriately, the word’s source is a Latin word meaning “elbow.”) Starting with the Wycliffe Bible in 1382, cubit has been used as the English translation for the measurement known in Biblical Hebrew as the “ammah” and in Koine as the “péchus.”