instrumental

adjective

Pronunciation: /ɪnstɹəˈmɛntəl/ / /ɪnstɹʊˈmɛntəl/

Etymology: From Middle English instrumental, instrumentale, from Medieval Latin īnstrūmentālis, equivalent to instrument + -al.

Essential or central; of great importance or relevance.
“He was instrumental in conducting the business.”
“The head is not more native to the heart, The hand more instrumental to the mouth”
Serving as an instrument, medium, means, or agency.
“Maxwell started back to his study, feeling that kind of satisfaction which a man feels when he has been even partly instrumental in finding an unemployed person a remunerative position.”
Pertaining to, made by, or prepared for an instrument, especially a musical instrument (rather than the human voice).
“instrumental music”
“an instrumental part”
Applied to a case expressing means or agency, generally corresponding to the English use of prepositions such as by, with, through, or by means of with the objective case.
“the instrumental case”

Etymology: From Middle English instrumental, instrumentale, from Medieval Latin īnstrūmentālis, equivalent to instrument + -al.

The instrumental case.
A composition written or performed without lyrics or singing, using a lead instrument to replace vocals.
“I recommend this album in the face of the fact that five of the eleven songs are the purest filler, dull instrumentals with a harmonica rifling over an indifferent rhythm section. The rest is magnificent […]”
A pause in the vocals of a song, usually occurring midway through, in which a musical instrument replaces the vocals.