The most common and most likely answer to this crossword clue is the 4 letter word FROM
F
R
O
M
Buddy explains!

The straight part
We know that "Off" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case off = from.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 FROM mean?
FROM preposition- Used to indicate source or provenance.
- Originating at (a year, time, etc.)
- Used to indicate a starting point or initial reference.
- Indicating removal or separation.
- Indicating exclusion.
- Indicating differentiation.
- Produced with or out of (a substance or material).
- Used to indicate causation; because of, as a result of.