The most common and most likely answer to this crossword clue is the 9 letter word GLISSANDO
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More clues leading to the result GLISSANDO
- Musical flourish modified signals at party
- Loading at sea keeps ship in rapid passage
- Furious loading keeps ship in rapid passage
- Sings do and la, after playing a slide of notes between them?
- Lad is struggling with song that has rapid succession of notes
- Series of notes for musician to travel around new islands
- Dormouse gets sulphur and oxygen on a sliding scale, perhaps
- Signals sent out before party producing such a musical effect
- Lass doing badly gets instruction for playing
- Air, rapidly ascending islands, turbulent throughout journey
Buddy explains!

The straight part
We know that "Musical flourish" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case musical flourish = glissando.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 GLISSANDO mean?
GLISSANDO noun- Either a continuous sliding from one pitch to another ("true" glissando), or an incidental scale played while moving from one melodic note to another ("effective" glissando).
- A method of playing an electric guitar in which a metal bar is held at right angles across the strings and rapidly moved up and down, creating a smooth, lush sound.
- To play with a glissando or sliding effect.