The most common and most likely answer to this crossword clue is the 8 letter word REMOTEST
R
E
M
O
T
E
S
T
More clues leading to the result REMOTEST
- More troubled by exam, becoming most withdrawn
- Soldiers needing medic, subject to stress: most faint
- Concerned with doctor and examination, most faint
- About to take second exam, becoming most uncommunicative
- Furthest little spot found in holiday?
- Extremely dubious book turned up in lounge
- Metres to helter-skelter? Extremely far
- Farthest spot among others
- More unusual ordeal, most unfriendly in manner
- Tiniest particle in balance
Buddy explains!

The straight part
We know that "Extremely dubious" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case extremely dubious = remotest.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 REMOTEST mean?
REMOTEST adjective- At a distance; disconnected.
- Distant or otherwise inaccessible.
- (especially with respect to likelihood) Slight.
- Emotionally detached.