ChatGPT said:
Cubit (UK)
The cubit is an ancient unit of length based on the distance from the elbow to the tip of the middle finger. In the UK, the cubit varied historically but was generally considered to be about 18 inches (approximately 45.72 centimeters).
The cubit was used in medieval England and earlier times for measuring lengths, especially in construction and tailoring. Itβs one of the oldest recorded units of measurement, with origins in ancient civilizations like Egypt and Mesopotamia.
Though obsolete in modern measurement systems, the cubit remains important in historical and archaeological contexts, reflecting early human methods of standardizing length based on the human body.
Summary:
1 cubit (UK) β 18 inches (45.72 cm)
Based on the length of the forearm
Used historically in construction and trade
Now mostly of historical interest