The most common and most likely answer to this crossword clue is the 10 letter word MELANOCYTE
I've seen this crossword clue in The Guardian
M
E
L
A
N
O
C
Y
T
E
Buddy explains!
The straight part
We know that "cell" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case cell = melanocyte.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 MELANOCYTE mean?
MELANOCYTE noun- A cell in the skin that produces the pigment melanin.