The most common and most likely answer to this crossword clue is the 5 letter word HOARD
I've seen this crossword clue in The Times
H
O
A
R
D
More clues leading to the result HOARD
- Difficult bottling oxygen for store
- Lay in cold, white shroud, close to ground
- Difficult to hide ring in collection
- Store’s now stopped plugging place
- Sort of frost on front of department store
- Possessing nothing, difficult to stockpile!
- Put away ball cutting forcefully
- Picked up Mob's store of money
- Save used tart, we're told
- Difficult, possessing nothing, to save
Buddy explains!

The straight part
We know that "Save" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case save = hoard.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 HOARD mean?
HOARD noun- A hidden supply or fund.
- A cache of valuable objects or artefacts; a trove.
- To amass, usually for one's own private collection.
- A hoarding (temporary structure used during construction).
- A hoarding (billboard).