The most common and most likely answer to this crossword clue is the 5 plus 2 letter word DREAM ON
I've seen this crossword clue in The Times
D
R
E
A
M
O
N
More clues leading to the result DREAM ON
- A modern resort? You wish!
- Nero mad, unrestrained? Highly unlikely
- That will never happen, road men at work
- Fellow holding papers? That won’t happen
- Fellow keeping the Queen up after midnight? That’s highly unlikely!
- Agree to get up around about morning – yeah, right!
- Doctor meeting Irishman with amputated foot? That’s hardly likely
- Lecturer bringing in about a million? You wish!
- That’s highly unlikely, say Watson and Holmes shortly
- It’s inconceivable academic keeps large quantity of paper
Buddy explains!
The straight part
We know that "That will never happen" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case that will never happen = dream on.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.