The most common and most likely answer to this crossword clue is the 9 letter word SCEPTICAL
I've seen this crossword clue in Financial Times
S
C
E
P
T
I
C
A
L
More clues leading to the result SCEPTICAL
- Foolishly accept lies without first bit of evidence? Unlikely to do that!.
- Caught in corrupt place? It's doubtful
- Dubious about entering sort of tank most of all
- Cold in beginning of autumn I term largely doubtful
- Questioning infected mobster full of cold
- Accepts I must change line that’s dubious
- Unwilling to give credit
- Doubting infected nearly everybody, including Catholic
- Doubtful about wearing infected animal’s skin
Buddy explains!

The straight part
We know that "Questioning" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case questioning = sceptical.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 SCEPTICAL mean?
SCEPTICAL adjective- Having, or expressing doubt; questioning.
- Of or relating to philosophical skepticism or the skeptics.