Si balneatrix non adest, nemo strigilem aut unguentum e mensa sumat.

It is a conditional sentence:

• Si balneatrix non adest = if the bath attendant is not present
• nemo ... sumat = let no one take ...

So the first clause gives the condition, and the second gives the instruction or prohibition that applies in that situation.

Yes. Si means if and normally introduces a condition.

Here it sets up the circumstance under which the command applies:

• Si balneatrix non adest = If the bath attendant is not present

This is very similar to English if.

Balneatrix is nominative singular because it is the subject of adest.

• balneatrix = the bath attendant (specifically a female bath attendant)
• adest = is present

So balneatrix is the person doing the being-present, which makes it the subject.

Adest comes from the verb adesse, meaning to be present or to be here.

It is a compound of:

• ad- = to, near
• est = is

So adest literally suggests is near / is present.

Grammatically, it is:

• 3rd person singular
• present tense
• indicative mood

So it means he/she/it is present. Here: the bath attendant is present.

Nemo means no one / nobody, so it works as a pronoun standing by itself.

Here it is the subject of sumat:

• nemo sumat = let no one take

By contrast, nullus usually works like an adjective meaning no or not any, and it normally modifies a noun:

• nullus servus = no slave
• nulla femina = no woman

Since the sentence means no one, not no person with a noun stated, nemo is the natural choice.

Because strigilem is in the accusative singular, the case used for the direct object of sumat.

The verb sumere means to take, so whatever is being taken goes into the accusative:

• strigilem = the scraper as the direct object
• unguentum = the ointment/oil as another direct object

So Latin is marking what no one is to take.

Because unguentum belongs to a different declension from strigilis.

• strigilis is a 3rd-declension noun, so its accusative singular is strigilem
• unguentum is a 2nd-declension neuter noun, and for neuter nouns the nominative and accusative singular are the same: unguentum

So both words are in the same case, but they look different because they follow different noun patterns.

Aut means or.

So:

• strigilem aut unguentum = the scraper or the ointment

If Latin used et, it would mean and instead:

• strigilem et unguentum = the scraper and the ointment

With nemo, the sense is that no one is to take either item.

E mensa means from the table.

The preposition e (or ex) means out of, from, and it takes the ablative case. That is why mensa is in the ablative singular.

So:

• e = from
• mensa = table in the ablative

Together: from the table

This is one of the most important grammar points in the sentence.

• sumit would be he/she takes — a simple statement
• sumat is present subjunctive

Here the subjunctive is used as a jussive subjunctive, which expresses a command or instruction in the third person:

• nemo sumat = let no one take

English does not usually have a special verb form for this, so we translate it with let.

Yes. The main clause is a negative command or prohibition:

• nemo ... sumat = let no one take ...

Latin often uses the present subjunctive for this kind of third-person command.

So the sentence is not merely describing what happens; it is telling people what must not happen.

Because the verb agrees with the subject, not with the objects.

The subject is nemo, which is grammatically singular:

• nemo = no one

The two accusatives, strigilem and unguentum, are just the things being taken. They do not control the number of the verb.

So singular sumat is exactly right.

Yes, the word order is normal, and yes, Latin could rearrange it.

This order is quite natural:

• Si balneatrix non adest — condition first
• nemo — subject of the command
• strigilem aut unguentum — the objects
• e mensa — where they are taken from
• sumat — verb at the end

Latin word order is more flexible than English because the endings show each word’s role. Still, putting the main verb at the end is very common and gives the sentence a neat, formal finish.