Plural of formula, especially used in scientific and mathematical contexts; multiple established procedures or mathematical expressions.
From Latin formula, 'small form,' with Latin plural formulae. English maintains the Latin plural in scientific writing, though 'formulas' is the English plural.
Formulae is the scholarly plural that scientists love—using it marks you as educated, but it also shows English's love-hate relationship with Latin; we borrow words then argue about whether to use their original plurals or Anglicize them.
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