|≈||approximately equal to|
|digits||indicates that digits repeat infinitely (e.g. 8.294 369 corresponds to 8.294 369 369 369 369 …)|
Earth radius is the distance from Earth's center to its surface, about 6,371 km (3,959 mi). This length is also used as a unit of distance, especially in astronomy and geology, where it is usually denoted by R⊕.
A finger (sometimes fingerbreadth or finger's breadth) is any of several units of measurement that are approximately the width of an adult human finger, including:
The digit, also known as digitus or digitus transversus (Latin), dactyl (Greek) or dactylus, or finger's breadth — 3⁄4 of an inch or 1⁄16 of a foot