The most common and most likely answer to this crossword clue is the 9 letter word TEMPERATE
I've seen this crossword clue in The Times
T
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More clues leading to the result TEMPERATE
- Sensible speed taken south of valley
- Leaving old city, fever becomes mild
- Benign mood overcomes troublesome female
- Paddy had a meal, balanced
- Rage at English being self-restrained
- Mild casual worker endlessly subjected to censure
- Clement worried by tendency to blow top
- Before charge, ancient wooded vale is calm
- Abstemious office worker’s energy and speed
- Teetotal locum associated with English judge
Buddy explains!

The straight part
We know that "Sensible" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case sensible = temperate.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 TEMPERATE mean?
TEMPERATE verb- To render temperate; to moderate
- Moderate; not excessive
- Moderate in the indulgence of the natural appetites or passions
- Proceeding from temperance.
- Living in an environment that is temperate, not extreme.