The most common and most likely answer to this crossword clue is the 9 letter word UNDERHAND
I've seen this crossword clue in The Times
U
N
D
E
R
H
A
N
D
More clues leading to the result UNDERHAND
- Dodgy, being at the mercy of cards one’s dealt
- Sneaky of the German, breaking free
- Displaying craft gift not enough?
- Working for a labourer is not straightforward
- Two foreign articles get signature in secret
- Deceptive
- Labourer’s assistant could be so devious
- Not straightforward when short of assistance
- Deceitful kind of bowling?
- Dishonest for a French worker to protect revolutionary communist
Buddy explains!

The straight part
We know that "Sneaky" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case sneaky = underhand.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 UNDERHAND mean?
UNDERHAND noun- The lower of two hands, the hand under the work.
- To toss or lob with an underhand movement.
- To trick, deceive or gull.
- To excavate downward in successive steps or horizontal slices while positioned above on unbroken ore.
- Secret; clandestine
- (by extension) dishonest and sneaky; done in a secret or sly manner
- (in various ball games, of a ball) thrown (etc.) with the hand brought forward and up from below
- With an underhand movement
- In a sly, sneaky or secret manner