The most common and most likely answer to this crossword clue is the 7 letter word EXPANSE
I've seen this crossword clue in The Times
E
X
P
A
N
S
E
More clues leading to the result EXPANSE
- Stretch of river occupied by vessels
- Centre for cost moved to a large region
- Sweep containers into river
- Stretch of river covering basins of salt
- Stretch and pull to pieces in peripheral half of exercise
- Width of river accommodating vessels
- Stretch of Devon river full of vessels
- Former partner strongly criticises European extension
- Swathe of attacks coming through river
- Width of river restricting vessels
Buddy explains!
The straight part
We know that "extension" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case extension = expanse.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 EXPANSE mean?
EXPANSE noun- A wide stretch, usually of sea, sky, or land.
- An amount of spread or stretch.