The most common and most likely answer to this crossword clue is the 3 letter word TAX
I've seen this crossword clue in The Times
T
A
X
More clues leading to the result TAX
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The straight part
We know that "Unrated" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case unrated = tax.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 TAX mean?
TAX noun- Money paid to the government other than for transaction-specific goods and services.
- A burdensome demand.
- A task exacted from one who is under control; a contribution or service, the rendering of which is imposed upon a subject.
- Charge; censure
- A lesson to be learned.
- To impose and collect a tax from (a person or company).
- To impose and collect a tax on (something).
- To make excessive demands on.
- To accuse.
- To examine accounts in order to allow or disallow items.