formality (n.)

In STYLISTIC and SOCIOLINGUISTIC studies, a dimension of social behavior ranging from the most strictly regulated to the least regulated, and reflected in language by varied linguistic features. Highly formal language involves carefully organized DISCOURSE, often with complex SYNTAX and vocabulary, which closely follows the STANDARD language, and which is often sensitive to PRESCRIPTIVE judgements. Highly informal language is very loosely structured, involving a high level of colloquial expression, and often departing from standard norms (e.g. by using slang, regionalisms, neologisms, and CODE-mixing).