The most common and most likely answer to this crossword clue is the 9 letter word CIVILISED
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More clues leading to the result CIVILISED
Buddy explains!

The straight part
We know that "Sophisticated" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case sophisticated = civilised.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 CIVILISED mean?
CIVILISED verb- To educate or enlighten a person or people to a perceived higher standard of behaviour.
- To introduce or impose the standards of one civilisation upon another civilization, group or person, arguably with the intent of achieving a perceived higher standard of behavior.
- To bring from a state of savagery to an educated or refined state.
- Having a highly developed society or culture.
- Showing evidence of moral and intellectual advancement; humane, reasonable, ethical.
- Marked by refinement in taste and manners.