noun

*pl.*-·las or -·lae·

- a fixed form of words, esp. one that has lost its original meaning or force and is now used only as a conventional or ceremonial expression: “Very truly yours” is a
*formula*used in letters - a rule or method for doing something, esp. when conventional and used or repeated without thought: a
*formula*for musical comedies - an exact statement of religious faith or doctrine
- directions for preparing a medicine, a paint, a baby's food, etc.
- something prepared from such directions; often specif., a milk preparation for feeding a baby

- a set of algebraic symbols expressing a mathematical fact, principle, rule, etc.: A = ?r is the
*formula*for determining the area of a circle - Chem. an expression of the composition of a compound (or a radical, etc.) by a combination of symbols and figures to show the constituents

Origin of formula

L, diminutive of*forma*, form