The most common and most likely answer to this crossword clue is the 8 letter word INTRUDER
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More clues leading to the result INTRUDER
- Trespasser at home initially turned more disrespectful
- Almost keen on less civil, unwelcome fellow
- Butter in hospital leaving taste less refined
- Perhaps one burgling home more loyal daughter interrupts
- Unexpected visitor rattled tin — not so polite
- Gatecrasher one less polite entertaining conservationists
- Unwelcome guest is, in time, less polite
- Trespasser in time gets less polite
- Unwelcome guest at home, more ill-mannered after drop of tequila
- Having gained power, Trump initially even more coarse – interloper!
Buddy explains!

The straight part
We know that "interloper" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case interloper = intruder.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 INTRUDER mean?
INTRUDER noun- Someone who intrudes.