For"mu*la (?), n.; pl. E. Formulas (#), L. Formulae (#). [L., dim. of forma form, model. SeeForm, n.]
1.
A prescribed or set form; an established rule; a fixed or conventional method in which anything is to be done, arranged, or said.
2. Eccl.
A written confession of faith; a formal statement of doctrines.
3. Math.
A rule or principle expressed in algebraic language; as, the binominal formula.
4. Med.
A prescription or recipe for the preparation of a medicinal compound.
5. Chem.
A symbolic expression (by means of letters, figures, etc.) of the constituents or constitution of a compound.
Chemical formulae consist of the abbreviations of the names of the elements, with a small figure at the lower right hand, to denote the number of atoms of each element contained.
Empirical formula Chem., an expression which gives the simple proportion of the constituents; as, the empirical formula of acetic acid is C2H4O2. -- Graphic formula, Rational formula Chem., an expression of the constitution, and in a limited sense of the structure, of a compound, by the grouping of its atoms or radicals; as, a rational formula of acetic acid is CH3.(C:O).OH; -- called also structural formula, constitutional formula, etc. See also the formula of Benzene nucleus, under Benzene. -- Molecular formula Chem., a formula indicating the supposed molecular constitution of a compound.
© Webster 1913.