instrumental /-mentˈl/ adjective

1. Acting as an instrument or means
2. Serving to promote an object
3. Helpful
4. Of, for, belonging to, or produced by, musical instruments
5. Relating to or done with an instrument
6. Denoting a type of learning process in which a particular response is always associated with a reinforcement, the response then intensifying (psychology)
7. Serving to indicate the instrument or means (grammar)

1. The instrumental case or a word in this case (grammar)
2. A piece of music for instruments only, ie without a vocal part

instrumentˈalism noun (philosophy)

A form of pragmatism associated with John Dewey

instrumentˈalist noun

1. A person who plays a musical instrument
2. A person skilled in the making of instruments
3. A person who believes in or advocates instrumentalism

instrumentality /-ment-alˈi-ti/ noun

Agency

instrumentˈally adverb

instrumentāˈtion noun

1. The use or provision of instruments
2. The arrangement of a composition for performance by different instruments, orchestration (music)

instrumenˈted adjective

Equipped with electronic, etc instruments

instrument flying noun

Navigation of aircraft in poor visibility by means of instruments only

instrument landing noun

Landing of aircraft in poor visibility by means of instruments and ground radio devices only

instrument panel or instrument board noun

A panel, eg in a car, on which instruments, dials, etc are mounted