The most common and most likely answer to this crossword clue is the 9 letter word FURROWING
I've seen this crossword clue in The Guardian
F
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More clues leading to the result FURROWING
Buddy explains!

The straight part
We know that "Making grooves" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case making grooves = furrowing.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 FURROWING mean?
FURROWING verb- To cut one or more grooves in (the ground, etc.).
- To wrinkle.
- To pull one's brows or eyebrows together due to concentration, worry, etc.
- A furrowed pattern.