The most common and most likely answer to this crossword clue is the 7 letter word SPOTTED
I've seen this crossword clue in The Sunday Telegraph
S
P
O
T
T
E
D
More clues leading to the result SPOTTED
Buddy explains!

The straight part
We know that "Saw/covered in roundish marks" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case saw/covered in roundish marks = spotted.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 SPOTTED mean?
SPOTTED verb- To see, find; to pick out, notice, locate, distinguish or identify.
- To loan a small amount of money to someone.
- To stain; to leave a spot (on).
- To remove, or attempt to remove, a stain.
- To retouch a photograph on film to remove minor flaws.
- To support or assist a maneuver, or to be prepared to assist if safety dictates.
- To keep the head and eyes pointing in a single direction while turning.
- To stain; to blemish; to taint; to disgrace; to tarnish, as reputation.
- To cut or chip (timber) in preparation for hewing.
- To place an object at a location indicated by a spot. Notably in billiards or snooker.
- Discoloured by spots; stained.
- (no comparative or superlative) Characterized by spots (used especially of animals and plants).