(mathematics) A number expressed in the decimal system (base ten), (particularly) fractional numbers so represented.

(algebra, number theory) A complex number (more generally, an element of a number field) that is a root of a polynomial whose coefficients are integers; equivalently, a complex number (or element of a number field) that is a root of a monic polynomial whose coefficients are rational numbers.

It is impossible to change people's habits, traits, or mindset.

(mathematics) Any real number that cannot be expressed as a ratio of two integers.

(idiomatic, obsolete) Used to form idioms meaning "to force someone to work hard or to focus intensely upon their work".

(idiomatic) Hard at work.

(music) A musical notation that indicates the relative duration of a note, using the color or shape of the note head, the presence or absence of a stem, and the presence of flags.

(physics) The ratio of the velocity of a body to that of sound in the surrounding medium.

A name that systematically designates a well-defined group of entities.

(law) a decree issued on a first petition for divorce; it becomes absolute at some later date unless cause is shown why it should not.