The arrangement of a musical composition for performance by a number of different instruments; orchestration; instrumental composition; composition for an orchestra or military band.

The act or manner of playing upon musical instruments; performance; as, his instrumentation is perfect.

What musical instruments will be used for performance

the instruments called for in a musical score or arrangement for a band or orchestra

the act of arranging a piece of music for an orchestra and assigning parts to the different musical instruments

The particular combination of instruments used in a piece of music. A string quartet's instrumentation is: two violins, viola and cello.

the combination of instruments used by musicians to play either a certain style of music, or a particular song within that genre. For example, a common instrumentation in a modern gospel choir is organ, piano, electric bass, drums, and the singers in the choir. An instrument that plays the melody of a song is often referred to as the lead instrument, and several instruments may restate this defining melody in the course of a performance. A musical style may be identified by its instrumentation and the way those instruments are played, although such criteria may appear in more than one genre.

the writing of music for particular instruments

The art of composing, arranging or orchestrating a piece for an ensemble.

The different types of instruments making up an ensemble.

The art of composing, orchestrating or arranging works for an instrumental ensemble.

Instrumentation is the study and practice of writing music for a musical instrument.