|≈||approximately equal to|
|digits||indicates that digits repeat infinitely (e.g. 8.294 369 corresponds to 8.294 369 369 369 369 …)|
The barleycorn is a small English unit of length equal to 1⁄3 of an inch (i.e., close to 0.8467 cm) still used in Great Britain and Ireland as a determiner of shoe sizes.
A metric foot is a nickname for a preferred number length of 3 basic modules (3 M), or 30 centimetres (11.811 in). The 30 cm metric ruler was a similar length to the traditional imperial one-foot ruler. A metric foot is 4.8 millimetres (0.189 in) shorter than an imperial foot.