The most common and most likely answer to this crossword clue is the 8 letter word INIMICAL
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More clues leading to the result INIMICAL
- Taken aback in lilac, I’m initially hostile
- Left endlessly bitter, given little, turning hostile
- At home this person’s in charge leading to endless talk, hostile
- Unfriendly but fashionable one goes to show without us
- Ridiculous claim to hold up popular setter as unfriendly
- Pernicious Cadillac I’m in is deficient in reverse
- Head of Institute finding nothing about glass substitute unfavourable
- I run away from criminal suspect with hostile attitude
- Skirt around a state of hostility
- Harmful material smuggled into Indiana and Illinois
Buddy explains!

The straight part
We know that "with hostile attitude" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case with hostile attitude = inimical.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 INIMICAL mean?
INIMICAL adjective- Harmful in effect.
- Unfriendly, hostile.