An example of a criterion is the set of guidelines for a thesis which is used to determine whether your thesis was good or bad.
nounpl. -·ria or -·ri·ons
Origin of criterionfrom Classical Greek krit?rion, means of judging from krit?s, judge; akin to kritikos: see critic
nounpl. cri·te·ri·a, or cri·te·ri·ons
Origin of criterionGreek kritērion from kritēs judge from krīnein to separate, judge ; see krei- in Indo-European roots.
Usage Note: Like phenomenon, criterion comes directly from Greek and is singular. In standard usage, the plural is generally criteria, although criterions is sometimes used as well. Properly speaking, the form criteria should never be a singular noun, and phrases like this criteria and single criteria are widely viewed as erroneous. Similarly, the plural criterias is also viewed as a mistake and is usually edited out of published prose.
- The plural form criterions also exists, but is much less common.
- The form criteria is sometimes used as a nonstandard singular form (as in a criteria, this criteria, and so on), with corresponding plural form criterias. In this use, it sometimes means “a single criterion”, sometimes “a set of criteria”.
From New Latin criterion, from Ancient Greek κριτήριον (kriterion, “a test, a means of judging”), from κριτής (krites, “a judge”), from κρίνω (krinō, “I judge”); see critic.