Myriad

In the context of numeric naming systems for powers of ten, myriad is the quantity ten thousand (10,000). Idiomatically, in English, myriad is an adjective used to mean that a group of things has indefinitely large quantity.

Myriad derives from the ancient Greek for ten thousand (μυριάς, myrias) and is used with this meaning in literal translations from Greek, Latin or Sinospheric languages (Chinese, Japanese, Korean, and Vietnamese), and in reference to ancient Greek numerals.

The term myriad is also used in the form "a myriad" for a 100 km × 100 km square (10,000 km²) the grid size of the British Ordnance Survey National Grid and the US Military Grid Reference System. It contains 100 hectads.