Synonyms for Formula (same or very similar meaning)
WordNet sense 1 (a representation of a substance using symbols for its constituent elements):
chemical formula
WordNet sense 2 (directions for making something):
recipe
WordNet sense 3 (a group of symbols that make a mathematical statement):
expression
WordNet sense 4 (something regarded as a normative example):
convention, normal, pattern, rule
From the ODE community, based on WordNet
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