The most common and most likely answer to this crossword clue is the 9 letter word HANDCRAFT
I've seen this crossword clue in The Times
H
A
N
D
C
R
A
F
T
More clues leading to the result HANDCRAFT
Buddy explains!

The straight part
We know that "Skill" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case skill = handcraft.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 HANDCRAFT mean?
HANDCRAFT noun- Handicraft
- The class of subjects for study that rely upon experimentation and observation.
- To engage in handcraft or handicraft.