The most common and most likely answer to this crossword clue is the 8 letter word COMEBACK
I've seen this crossword clue in Independent
C
O
M
E
B
A
C
K
More clues leading to the result COMEBACK
- What rock bands may make, some of them occasionally?
- Extend help in return
- Play the part of Obama spurning soldiers with quick reply
- Sally‘s heavenly body almost touching rugby player
- Order starter of Big Mac and Coke? Recrimination results
- Firm note in past taken as rejoinder
- Revival of firm needing this person
- Quick answer for invitation to return
- Return in rally
- Answer: Boomerang
Buddy explains!

The straight part
We know that "Sally" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case sally = comeback.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 COMEBACK mean?
COMEBACK noun- A return (e.g. to popularity, success, etc.) after an extended period of obscurity.
- A retort or answer, particularly a quick or clever one.
- An occurrence of an athlete or sports team in a competition overcoming a substantial disadvantage in points to win or draw.