The most common and most likely answer to this crossword clue is the 7 letter word SOAKING
I've seen this crossword clue in The Sunday Telegraph
S
O
A
K
I
N
G
More clues leading to the result SOAKING
Buddy explains!

The straight part
We know that "Wet" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case wet = soaking.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 SOAKING mean?
SOAKING verb- To be saturated with liquid by being immersed in it.
- To immerse in liquid to the point of saturation or thorough permeation.
- To penetrate or permeate by saturation.
- To allow (especially a liquid) to be absorbed; to take in, receive. (usually + up)
- To take money from.
- To drink intemperately or gluttonously.
- To heat (a metal) before shaping it.
- To hold a kiln at a particular temperature for a given period of time.
- To absorb; to drain.
- Immersion in water; a drenching or dunking.
- Extremely wet; saturated.