The most common and most likely answer to this crossword clue is the 10 letter word GRAMMARIAN
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More clues leading to the result GRAMMARIAN
- Old lady hosting male Spanish virgin is a stickler for rules
- Eg Fowler's old lady transfixed by married woman
- With good memory, lover has name of word expert
- Expert on 8 etc seeing maid put on weight
- Language specialist puts together Mass, one devoted to Our Lady
- A bookish sort, Margaret returned Robin’s love
Buddy explains!

The straight part
We know that "A bookish sort" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case a bookish sort = grammarian.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 GRAMMARIAN mean?
GRAMMARIAN noun- A person who studies grammar.