The most common and most likely answer to this crossword clue is the 12 letter word INSTRUMENTAL
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More clues leading to the result INSTRUMENTAL
- There are no words to express such music!
- Endless tune a minstrel composed, music without words
- Like some pieces, playing a part
- Altering manner, lutist produces musical piece
- No words are sung in this key
- Offering help of the orchestra, for example?
- Wandering minstrel with a tune, mostly musical piece
- Like orchestral music, in turn, is awfully cerebral
- Helpful turn is somehow ridiculous
- One's responsible as one turns out to be crazy
Buddy explains!

The straight part
We know that "No words are sung in this/key" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case no words are sung in this/key = instrumental.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does INSTRUMENTAL mean?
INSTRUMENTAL noun- (grammar) The instrumental case.
- A composition written or performed without lyrics, sometimes using a lead instrument to replace vocals.
- Essential or central; of great importance or relevance.
- Pertaining to, made by, or prepared for, an instrument, especially a musical instrument (rather than the human voice).
- (grammar) Applied to a case expressing means or agency, generally indicated in English by by or with with the objective.