The most common and most likely answer to this crossword clue is the 5 letter word EATEN
I've seen this crossword clue in The Times
E
A
T
E
N
More clues leading to the result EATEN
- Taken in and defeated, but not bowled
- School's picked up, as courses enjoyed?
- We hear school’s taken in
- Defeated, beheaded and consumed
- Polished off school broadcast
- Worried, starting off on the losing side?
- Put away or tidy last of autumn leaves
- It’s said school for the rich scoffed
- What’s in tea tent — to be this?
- Dean flayed by cardinal and devoured
Buddy explains!

The straight part
We know that "Polished off" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case polished off = eaten.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 EATEN mean?
EATEN verb- To ingest; to be ingested.
- To use up.
- To cause (someone) to worry.
- To take the loss in a transaction.
- To be injured or killed by (something such as a firearm or its projectile), especially in the mouth.
- To corrode or erode.
- To perform oral sex (on a person or body part).
- (especially in combination) That has been consumed by eating