The most common and most likely answer to this crossword clue is the 1 plus 5 plus 2 plus 2 plus 10 letter word A WOMAN OF NO IMPORTANCE
I've seen this crossword clue in The Times
A
W
O
M
A
N
O
F
N
O
I
M
P
O
R
T
A
N
C
E
Buddy explains!
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.