|≈||approximately equal to|
|digits||indicates that digits repeat infinitely (e.g. 8.294 369 corresponds to 8.294 369 369 369 369 …)|
An attometer is a unit of length, a combination of the metric prefix atto (symbol a) and the SI unit of length meter (symbol m), equal to 10−18 meter or 1.0E-18 meter and its symbol is am. Plural name is attometers.
The cubit is an ancient unit based on the forearm length from the tip of the middle finger to the bottom of the elbow. Cubits of various lengths were employed in many parts of the world in antiquity, during the Middle Ages and as recently as Early Modern Times. The term is still used in hedge laying, the length of the forearm being frequently used to determine the interval between stakes placed within the hedge.