The most common and most likely answer to this crossword clue is the 7 letter word HOLLOWS
I've seen this crossword clue in The Guardian
H
O
L
L
O
W
S
Buddy explains!
The straight part
We know that "craters" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case craters = hollows.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 HOLLOWS mean?
HOLLOWS noun- A small valley between mountains.
- A sunken area or unfilled space in something solid; a cavity, natural or artificial.
- A sunken area.
- A feeling of emptiness.
- To make a hole in something; to excavate
- To call or urge by shouting; to hollo.