The most common and most likely answer to this crossword clue is the 7 letter word THOREAU
T
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More clues leading to the result THOREAU
- French writer, still with regiment, put on a uniform
- One who wrote article about gold in one form and another
- Embracing Aristotle’s conclusion, author turned philosopher
- US writer’s thunderous god over water in France
- English author upset American one
- US writer, author switching parts without energy
- Versed in books no end? You must get hold of that American author
- Philosopher representing the precious metal, including its colour
- Author abroad
- Our heart breaks taken right out of his writing
Buddy explains!

The straight part
We know that "Writer of “Walden”" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case writer of “walden” = thoreau.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.