Formal, (adj.) relating to an established procedure or set of specific behaviors.

For other uses of form see Form

For other uses of formalism see Formalism

Formal may also refer to:

General:

• Formal (university), a type of ceremonial event at university
• School formal, a type of ceremonial event at school
• Formal wear, clothing for formal occasions
• Informal sector, as opposed to Formal sector, economic activity beyond the purview of government
• A Formality, an established procedure or set of specific behaviors

Logic and mathematics:

• Formal logic, logical argument based on form
• Formal cause, Aristotle's intrinsic, determining cause
• Formal power series, a generalization of power series without requiring convergence, used in combinatorics
• Formal calculation, a calculation which is systematic, but without a rigorous justification
• Formal set theory, as opposed to Naive set theory
• Formal derivative, an operation on elements of a polynomial ring which mimics the form of the derivative from calculus

Linguistics:

• Formal system, an abstract means of generating inferences in a formal language
• Formal language, comprising the symbolic "words" or "sentences" of a formal system
• Formal grammar, a grammar describing a formal language
• Formal proof, a fully rigorous proof as is possible only in a formal system
• Dynamic and formal equivalence word-for-word translation, especially of the Bible

Chemistry:

• Formaldehyde, short form for, also formalin
• Dimethoxymethane, a synonym for this
• Concentration, a unit of concentration (F) similar to molarity

Computer science:

• Formal methods, mathematically-based techniques for the specification, development and verification of software and hardware systems
• Formal specification, describes what a system should do, not how it should do it
• Formal verification, proves correctness of a system