The most common and most likely answer to this crossword clue is the 6 letter word BACKUP
I've seen this crossword clue in The Guardian
B
A
C
K
U
P
More clues leading to the result BACKUP
Buddy explains!
The straight part
We know that "Support/reverse" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case support/reverse = backup.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 BACKUP mean?
BACKUP noun- A reserve or substitute.
- A copy of a file or record, stored separately from the original, that can be used to recover the original if it is destroyed or damaged.
- An accumulation of material caused by a (partial) obstruction or (complete) blockage of the flow or movement of the material, or an accumulation of material that causes an overflow due to the flow being greater than the maximum possible flow.
- (law enforcement) reinforcements
- Standby, reserve or extra.
- That is intended as a backup.
- Supporting, reinforcing; of or related to accompaniment