What is the meaning of formula?

noun

• A group of symbols that make a mathematical statement.
  • synonyms: expression
• Directions for making something.
  • synonyms: recipe
• A conventionalized statement expressing some fundamental principle.
• A representation of a substance using symbols for its constituent elements.
  • synonyms: chemical formula
• Something regarded as a normative example.
  • usage: "the convention of not naming the main character"; "violence is the rule not the exception"; "his formula for impressing visitors"
  • synonyms: convention, normal, pattern, rule
• A liquid food for infants.
• Mathematics) a standard procedure for solving a class of mathematical problems. (
  • usage: "he determined the upper bound with Descartes' rule of signs"; "he gave us a general formula for attacking polynomials"
  • synonyms: rule