A formula used in atomic physics to describe the wavelengths of spectral lines of many chemical elements.

(mathematics) A formula for calculating the sum of an arithmetical function by means of an inverse Mellin transform.

(religion, Christianity) The phrase "in the name of the Father, and of the Son, and of the Holy Spirit", or words to that form and effect, referring to the three persons of the Christian Trinity.

(physics) An equation used to calculate the flow velocity of a fluid in an open-channel system, relating Chezy's coefficient to variables such as radius, roughness, and discharge.

(organic chemistry) A skeletal formula, especially a schematic representation of benzene as a hexagon made up of alternating single and double lines that represent alternating single and double bonds

(chemistry) A structural formula which is reduced (i.e., skeletal) in the sense that carbon atoms forming the backbone of the structure (esp. of an organic compound) are not labeled — they are shown simply as vertices — and hydrogen atoms are not shown at all (except those which are bonded to heteroatoms, or the exceptionally labeled carbon atoms) but heteroatoms are always labeled. (Labels of labeled hydrogen atoms are written next to labels of the atoms that they are bonded to, without a bond drawn between them. If there are several labeled hydrogen atoms bonded to the same atom then they are written as an H with a subscript for their number.) Carbon atoms which are (optionally) labeled tend to be in reactive extremities of the molecule, not the backbone of it.

(logic) A well-formed formula which has not been made by combining simpler well-formed formulas by means of logical connectives.

plural of distance formula

(trigonometry) law of cosines

(trigonometry) law of sines