The most common and most likely answer to this crossword clue is the 9 letter word PATTERNED
I've seen this crossword clue in The Daily Telegraph
P
A
T
T
E
R
N
E
D
Buddy explains!

The straight part
We know that "Fancy" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case fancy = patterned.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 PATTERNED mean?
PATTERNED verb- To apply a pattern.
- To make or design (anything) by, from, or after, something that serves as a pattern; to copy; to model; to imitate.
- To follow an example.
- To fit into a pattern.
- To serve as an example for.
- Conformed to a pattern, a model to be followed.
- Supplied with a pattern