The most common and most likely answer to this crossword clue is the 7 letter word ICINESS
I've seen this crossword clue in The Times
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More clues leading to the result ICINESS
- Here in France, head shows hostile attitude
- Hostility as I film bodyguard
- Distance from here to Paris, then Cape
- Reserve medicines — spare bottles
- In charge, one head showing hostility
- Reserve shown by old company head
- Chill requires drugs — first three failed, then one succeeded
- Extreme coldness of nice sis changed for the worse
- Former chemical business head’s hostility
- Primarily, inheritance tax is to circumvent popular indifference
Buddy explains!

The straight part
We know that "Hostility" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case hostility = iciness.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.