The most common and most likely answer to this crossword clue is the 8 letter word UNCOUPLE
I've seen this crossword clue in The Sunday Telegraph
U
N
C
O
U
P
L
E
More clues leading to the result UNCOUPLE
- Break link with relative about publisher
- Divorce de Monsieur et Madame?
- Separate northern takeover, in principle, not right
- United, Poulenc incited divorce
- Peacemakers get pair to separate
- Release a French pair
- Separate a continental pair
- Ring up boring relative for free
- Release articles in French about hostile takeover
- Stumbling upon clue for ‘disconnect’
Buddy explains!

The straight part
We know that "Release" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case release = uncouple.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 UNCOUPLE mean?
UNCOUPLE verb- To disconnect or detach one thing from another.
- To come loose.
- To loose, as dogs, from their couples.