The most common and most likely answer to this crossword clue is the 7 letter word OUTLIER
I've seen this crossword clue in The Daily Telegraph
O
U
T
L
I
E
R
More clues leading to the result OUTLIER
- Isolated figure to expose ‘fake news king’
- A peripheral figure to unmask reputedly dishonest character
- Oxford University row about learner, one having no connections
- Metal with external shielding is an exception
- Point away from the crowd to expose fabrication by Republican
- Rue toil, possibly, as one living a long way from work
- Isolated rock from Route 51
- Expose and rile eccentric office worker with a long commute?
Buddy explains!

The straight part
We know that "one having no connections" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case one having no connections = outlier.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 OUTLIER mean?
OUTLIER noun- A person or thing situated away from the main body or outside its proper place.
- A part of a formation separated from the rest of the formation by erosion.
- A value in a statistical sample which does not fit a pattern that describes most other data points; specifically, a value that lies 1.5 IQR beyond the upper or lower quartile.