The most common and most likely answer to this crossword clue is the 7 letter word FRESCOS
I've seen this crossword clue in The Daily Telegraph
F
R
E
S
C
O
S
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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 FRESCOS mean?
FRESCOS noun- A cool, refreshing state of the air; coolness, duskiness, shade.
- An artwork made by applying water-based pigment to wet or fresh lime mortar or plaster.
- The technique used to make such an artwork.