(mathematics) The number of possible paths from the southwest corner (0, 0) of a rectangular grid to the northeast corner (m, n), using only single steps north, northeast, or east.

(chemistry) A measurement of the basicity of an oil, expressed in terms of the number of milligrams of potassium hydroxide per gram of oil sample.

A unique number which identifies a published book, for example, an ISBN.

A number assigned to each work composed by Wolfgang Amadeus Mozart.

(telecommunications) A number denoting the electrical load of a telephone ringer circuit on a particular line.

(seduction community) To end a pickup of a woman by getting her telephone number.

(seduction community) The successful acquisition of a woman's telephone number at the end of a pickup attempt.

A number that represents the reciprocal of the dispersive power of a substance with transparent qualities.

(mathematics, algebraic number theory) A field which includes the rational numbers and has finite dimension as a vector space over the rational numbers.

An extremely large number that is an upper bound on the solution to a certain problem in Ramsey theory.