The most common and most likely answer to this crossword clue is the 6 letter word WILLIE
I've seen this crossword clue in Financial Times
W
I
L
L
I
E
Buddy explains!
The straight part
We know that "Women’s organisation accepts sick European as / (6)" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case women’s organisation accepts sick european as / (6) = willie.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 WILLIE mean?
WILLIE noun- (hypocoristic) the penis.
- Term of abuse.
- A person who is manipulated into serving as a useful agent without knowing it.