The most common and most likely answer to this crossword clue is the 9 letter word NEFARIOUS
I've seen this crossword clue in The Times
N
E
F
A
R
I
O
U
S
More clues leading to the result NEFARIOUS
- Wicked Olympic city unfortunately unsafe to tour
- Developed for use in a base
- Criminal female comes in handy with debtor's notes
- Moving of one near US base
- Wicked cracking safe in court interior
- Wicked of a nurse to go off without one
- Are fusion bombs immoral?
- Extremely wicked fellow breaks stingy promises
- Evil location of 28’s remote debts?
- Fire on a makeshift American base
Buddy explains!
The straight part
We know that "base" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case base = nefarious.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 NEFARIOUS mean?
NEFARIOUS adjective- Sinful, villainous, criminal, or wicked, especially when noteworthy or notorious for such characteristics.