The most common and most likely answer to this crossword clue is the 5 letter word GAVEL
I've seen this crossword clue in The Guardian
G
A
V
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L
More clues leading to the result GAVEL
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The straight part
We know that "something at auction" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case something at auction = gavel.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 GAVEL mean?
GAVEL noun- Rent.
- Usury; interest on money.
- An old Saxon and Welsh form of tenure by which an estate passed, on the holder's death, to all the sons equally.
- To divide or distribute according to the gavel system.
- A wooden mallet, used by a courtroom judge, or by a committee chairman, struck against a sounding block to quieten those present, or by an auctioneer to accept the highest bid at auction.
- (metonymically) The legal system as a whole.
- A mason's setting maul.
- To use a gavel.
- A small heap of grain, not tied up into a bundle.
- A gable.