The most common and most likely answer to this crossword clue is the 10 letter word APOSTROPHE
I've seen this crossword clue in The Daily Telegraph
A
P
O
S
T
R
O
P
H
E
More clues leading to the result APOSTROPHE
- Bloomingdale's gets one out to a shopper
- Address in Bishop’s Stortford
- Punctuation mark perhaps too irregular
- Mark small extract from Eugene O’Neill
- It’s often abused by grocers dealing with multiples
- If letters were missing, this could be the fourth character of eight in a string
- Support right in a forlorn hope – sign of lack of character?
- Punctuation mark, perhaps too complicated?
- Punctuation mark, perhaps too misused
- Pope rash to change punctuation
Buddy explains!

The straight part
We know that "You can see me in John o’ Groats, and in Land’s End, but not in between!" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case you can see me in john o’ groats, and in land’s end, but not in between! = apostrophe.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 APOSTROPHE mean?
APOSTROPHE noun- The text character ’, which serves as a punctuation mark in various languages and as a diacritical mark in certain rare contexts.
- A sudden exclamatory piece of dialogue addressed to someone or something, especially absent.