The most common and most likely answer to this crossword clue is the 3 plus 4 letter word ELM TREE
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More clues leading to the result ELM TREE
- Term wasted with eel that’s prone to disease
- Having shed sides in the way, nightmarish location for plant
- Saint coming out of film studio including Moore’s debut that’s thoroughly wooden
- Wood taking minutes instead of seconds in film studios
- Having lost both axes, extremely tricky to get wood
- Regularly tells mate about English timber supplier
Buddy explains!

The straight part
We know that "that’s thoroughly wooden" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case that’s thoroughly wooden = elm tree.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.