The most common and most likely answer to this crossword clue is the 9 letter word INFATUATE
I've seen this crossword clue in Independent
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More clues leading to the result INFATUATE
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The straight part
We know that "entrance" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case entrance = infatuate.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 INFATUATE mean?
INFATUATE noun- Infatuated person.
- To inspire with unreasoning love, attachment or enthusiasm.
- To make foolish.
- Infatuated, foolishly attracted to (someone).
- Foolish, lacking good judgement.