difference Criterion vs Criterium [closed]

Criterion is something used to help make a judgement or decision

Criterium is a bike race

tl;dr: You in general want criterion, criteria, because criterium, criteriums is a very specialized term.

The normal word is criterion, criteria, which per Oxford Dictionaries Online means “a principle or standard by which something may be judged or decided.” The specialized U.S. term criterium, criteriums is again per Oxford “a one-day bicycle race on a circuit road course.”

The singular noun corresponding to the plural noun criteria is criterion. These are from the Greek, where you see -ion, -ia for singular and plural.

The term criterium comes to us from French. It's a kind of bicycle circuit race. Per Wiktionary it derives from:

From French critérium ‎(“competition”), from Late Latin criterium, from Ancient Greek κριτήριον ‎(kritḗrion).

With further explanation from Wikipedia:

A criterium, or crit, is a bike race consisting of several laps around a closed circuit, the length of each lap or circuit ranging from about 1 km to 2 km.