The most common and most likely answer to this crossword clue is the 11 letter word GENEALOGIST
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More clues leading to the result GENEALOGIST
- I study trees and gloat seeing larks around
- Tree student has info on each branch first
- A record is kept by French author who may explore a particular line
- Polite chap lagging each trunk is tree expert
- Who’s got lineages sorted out?
- Lineages got from him? Yes
- Student of descent makes owner of ‘Champion the W.H.’ see the point
- Family history buff got lineages wrong
Buddy explains!

The straight part
We know that "who may explore a particular line" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case who may explore a particular line = genealogist.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 GENEALOGIST mean?
GENEALOGIST noun- A person who studies or practises genealogy, an expert in genealogy.