Restat ut magister auctionis rem emptori addicat.

Together, restat ut means something like it remains that..., it only remains for..., or more idiomatically all that is left is for...

So in this sentence, Restat ut magister auctionis rem emptori addicat means:

• It remains for the auctioneer to award the item to the buyer
• or All that is left is for the auctioneer to knock down the item to the buyer

Latin often uses restat ut + subjunctive where English would prefer it remains to... or all that is left is for...

Because it is inside an ut-clause depending on restat.

After expressions like restat ut, Latin regularly uses the subjunctive. The idea is not simply a plain statement of fact, but the action that still remains to be done.

So:

• restat = it remains
• ut ... addicat = that ... should award / to award

Here addicat is present subjunctive active, 3rd person singular, from addicere.

Latin often expresses this idea with a full clause, not just an infinitive.

English says:

• It remains for the auctioneer to award the item

Latin says:

• Restat ut magister auctionis rem emptori addicat

So instead of using a bare infinitive like to award, Latin uses ut + subjunctive. That is just the normal construction after restat in this sense.

The subject is magister auctionis.

Since addicat is 3rd person singular, we look for a singular nominative noun, and that is magister.

So:

• magister = the master / manager / auctioneer
• auctionis = of the auction

Together, magister auctionis means the auctioneer or more literally the master of the auction.

• magister is nominative singular, the subject.
• auctionis is genitive singular, modifying magister.

So literally:

• magister auctionis = the master of the auction

The genitive auctionis shows possession or association: of the auction.

Because addicere takes:

• the thing awarded in the accusative
• the person to whom it is awarded in the dative

So here:

• rem = the thing / property / item in the accusative singular
• emptori = to the buyer in the dative singular

That gives the pattern:

• rem emptori addicat = award the item to the buyer

This is very common in Latin: accusative for the direct object, dative for the indirect object.

In this context, addicere is a technical word meaning to adjudge, award, assign, or at an auction to knock down to the successful bidder.

So this is not just a vague say or declare. It means the official act of assigning the item to the buyer.

In an auction context, a very natural English rendering is:

• award the item to the buyer
• knock down the lot to the buyer

Res is a very common Latin noun meaning thing, matter, affair, property, or object, depending on context.

Here, because the sentence is about an auction, rem most naturally means:

• the item
• the property
• the thing being sold

It is the accusative singular form of res.

Yes. Emptori is the dative singular of emptor, which means buyer or purchaser.

The forms are:

• emptor = buyer
• emptoris = of the buyer
• emptori = to/for the buyer

So in this sentence, emptori means to the buyer.

A word-for-word layout is:

• Restat = it remains
• ut = that / for ... to
• magister auctionis = the auctioneer
• rem = the item
• emptori = to the buyer
• addicat = award

So literally:

• It remains that the auctioneer award the item to the buyer

Latin word order is much freer than English word order because the endings show the grammatical roles. Putting addicat at the end is very normal Latin style. It lets the sentence build up to the main action.

Yes. Several translations are possible, depending on how literal or idiomatic you want to be.

Possible translations include:

• It remains for the auctioneer to award the item to the buyer.
• All that remains is for the auctioneer to assign the property to the buyer.
• It only remains for the auctioneer to knock down the item to the buyer.

A very literal translation is:

• It remains that the auctioneer award the thing to the buyer.

But that sounds less natural in English.

It mainly expresses what still remains to be done.

So the idea is not exactly:

• a command
• a future tense statement
• or a moral obligation

Instead, it means:

• this is the remaining step in the process

That is why restat ut works well here: it marks the final action still pending.