The most common and most likely answer to this crossword clue is the 9 letter word DESCRIBES
I've seen this crossword clue in The Guardian
D
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More clues leading to the result DESCRIBES
Buddy explains!
The straight part
We know that "marks out" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case marks out = describes.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 DESCRIBES mean?
DESCRIBES verb- To represent in words.
- To represent by drawing; to draw a plan of; to delineate; to trace or mark out.
- To give rise to a geometrical structure.
- To introduce a new taxon to science by explaining its characteristics and particularly how it differs from other taxa.
- To distribute into parts, groups, or classes; to mark off; to class.