The most common and most likely answer to this crossword clue is the 2 plus 2 plus 4 letter word GO TO TOWN
I've seen this crossword clue in The Daily Telegraph
G
O
T
O
T
O
W
N
More clues leading to the result GO TO TOWN
- Act enthusiastically, but not be in Hamlet?
- Take the up train and have a great time
- Dorothy’s dog, all dressed up for a party, wanting to make the most of it
- To do well, shift about two religious texts
- Dress-wearing friend of Dorothy is to proceed enthusiastically
- Splash out, putting dress on Dorothy’s dog . . . .
- Get stuck in journey London bound?
- Act enthusiastically when Dorothy’s companion turns up in a dress
- Frocked friend of Dorothy let rip
- Dorothy’s companion in dress let hair down?
Buddy explains!
The straight part
We know that "let rip" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case let rip = go to town.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.