adjective
In accordance with established forms.
Official.
Relating to the form or structure of something.
Relating to formation.
Ceremonial or traditional.
Proper, according to strict etiquette; not casual.
Organized; well-structured and planned.
(especially sciences, mathematics, linguistics) In accordance with a methodological framework with well-defined rules or laws; rigorous.
(mathematics, philosophy) Relating to mere manipulation and construction of strings of symbols, without regard to their meaning.
noun
(clothing) An evening gown.
An event with a formal dress code.
(programming) A formal parameter.
(Oxbridge slang) Ellipsis of formal hall.
noun
(uncountable) Formalin.
An acetal formed from formaldehyde.