Meaning of FORMAL in English
1》 done in accordance with rules of convention or etiquette.
↘having a conventionally recognized form, structure, or set of rules: he had little ~ education.
↘of or denoting a style of writing or public speaking characterized by more elaborate grammatical structures and more conservative and technical vocabulary.
2》 officially recognized: a ~ complaint.
3》 of or concerned with outward form rather than content.
↘having a form or appearance but no true function: the committee stage would be purely ~.
↘relating to linguistic or logical form as opposed to function or meaning.
■ noun N. Amer. an evening dress.
↘an occasion on which evening dress is worn.
ME: from L. ~is , from forma (see form ).
Concise Oxford English vocab. Сжатый оксфордский словарь английского языка. 2004