instrumental

American  

[in-struh-men-tl] / ˌɪn strəˈmɛn tl /

adjective

1. serving or acting as an instrument or means; useful; helpful.

   Synonyms:

   effective, effectual, implemental

2. performed on or written for a musical instrument or instruments.

   instrumental music.

3. of or relating to an instrument or tool.

4. Grammar.

   1. (in certain inflected languages, as Old English and Russian) noting or pertaining to a case having as its distinctive function the indication of means or agency, as Old English beseah blīthe andweitan “looked with a happy countenance.”

   2. noting the affix or other element characteristic of this case, or a word containing such an element.

   3. similar to such a case form in function or meaning, as the Latin instrumental ablative, gladiō, “by means of a sword.”

   4. (in case grammar) pertaining to the semantic role of a noun phrase that indicates the inanimate, nonvolitional, immediate cause of the action expressed by a verb, as the rock in The rock broke the window or in I broke the window with the rock.

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noun

1. Grammar.

   1. the instrumental case.

   2. a word in the instrumental case.

   3. a construction of similar meaning.

2. a musical composition played by an instrument or a group of instruments.

instrumental British  

/ ˌɪnstrəˈmɛntəl /

adjective

1. serving as a means or influence; helpful

2. of, relating to, or characterized by an instrument or instruments

3. played by or composed for musical instruments

4. grammar denoting a case of nouns, etc, in certain inflected languages, indicating the instrument used in performing an action, usually translated into English using the prepositions with or by means of

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noun

1. a piece of music composed for instruments rather than for voices

2. grammar

   1. the instrumental case

   2. a word or speech element in the instrumental case

Other Word Forms

• instrumentality
  noun
• instrumentally
  adverb
• noninstrumental
  adjective
• noninstrumentally
  adverb
• uninstrumental
  adjective
• uninstrumentally
  adverb

Etymology

Origin of instrumental

First recorded in 1350–1400; Middle English word from Medieval Latin word instrūmentālis. See instrument, -al ¹

Explanation

Instrumental music involves just instruments — no singing. But you could also say that the conductor is instrumental to — or a critical part of — an orchestra's success. If you enjoy the ballet, part of it may be the instrumental music that accompanies the graceful movements. An instrumental song is one without a singer, and there can be instrumental passages of any song, where the band just plays and the singer is quiet. But this word also means something like useful. You could say that Martin Luther King, Jr. was an instrumental part of the civil rights movement because he was such an important part of it.

Example Sentences

The witness most instrumental to Fernandez’s conviction also admitted at trial to a history of lying in court.

From Slate • May 29, 2026

Yet some Hong Kong entities play an instrumental role in efforts to flout restrictions, according to a new report by the China Strategic Risks Institute, a London-based think tank.

From The Wall Street Journal • May 28, 2026

Glass has written a significant quantity of pure music for a vast range of instrumental forces from multiple genres and cultures.

From Los Angeles Times • May 21, 2026

This discussion should not only outline your value outside the company, but also identify how you’ve been instrumental in helping your company meet its goals.

From MarketWatch • May 20, 2026

When the Haudenosaunee hunted these animals, the historian William Cronon observed, they were harvesting a foodstuff which they had consciously been instrumental in creating.

From "1491" by Charles C. Mann

Related Words

• involved