The most common and most likely answer to this crossword clue is the 9 letter word LARGHETTO
I've seen this crossword clue in The Guardian
L
A
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G
H
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T
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O
More clues leading to the result LARGHETTO
- Instruction for players, both sides admitting a poor quarter
- Run into US city slum at a leisurely pace
- Such a movement with added energy could be altogether different
- Line to gather unravels quite slowly
- King enters city slum quite deliberately
- Somewhat slow, Republican to enter US city slum area
- Slowish piece altogether played with insufficient energy
- Say, Dharavi for example is cleared — the movement will be slow
- Relatively slow section from storyteller primarily illustrates lost, poor part of city
Buddy explains!

The straight part
We know that "quite deliberately" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case quite deliberately = larghetto.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 LARGHETTO mean?
LARGHETTO noun- The larghetto tempo.
- A composition or movement to be played larghetto.
- Slower than adagio but not as slow as largo; nearly andantino.