The most common and most likely answer to this crossword clue is the 9 letter word LIBRARIAN
I've seen this crossword clue in Independent
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More clues leading to the result LIBRARIAN
- Lender almost smiling: it’s on the house!
- Politician, Republican, heretic -- one looking after books
- Sign to precede terrible rain? I may help you find the literature
- Literary minder
- Book expert, one under one zodiacal sign not initially following another
- British Rail in a mix-up with employee in Reading office?
- Bookish type, one born at the end of September, back in his element? On the contrary!
- Bookkeeper’s sign represented rain
- Some stars look up new person to look after the books
- Sign managed to stifle one worker in quiet environment?
Buddy explains!

The straight part
We know that "employee in Reading office?" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case employee in reading office? = librarian.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 LIBRARIAN mean?
LIBRARIAN noun- The keeper, manager of a library.
- One who cares for the publications, files etc. in a library, whether staff or volunteer.
- A person who processes and organizes information.