Testator heredem palam nuncupat.

Testator is nominative singular, which is the case normally used for the subject of a sentence.

You can tell it is the subject because:

• it is in the nominative,
• the verb nuncupat is 3rd person singular, and
• testator is the noun that fits as the doer of the action.

So testator = the testator / the person making the will.

Because heredem is in the accusative singular, not the nominative.

The basic dictionary form is heres = heir.
But in this sentence, the heir is the direct object of nuncupat, so Latin puts it in the accusative:

• nominative: heres
• accusative: heredem

So heredem means an heir or the heir as the thing being named or declared.

Both are third-declension nouns.

Their forms here are:

• testator: nominative singular
• heredem: accusative singular of heres

A learner may notice that these do not look like first- or second-declension nouns such as puella or servus. That is normal: third declension has a wider variety of endings and stems.

Palam is an adverb. It means openly, publicly, or plainly.

It modifies the verb nuncupat, telling you how the naming or declaration is done.

So:

• nuncupat = he names / declares
• palam nuncupat = he names / declares openly or publicly

Nuncupat is:

• present tense
• active voice
• indicative mood
• 3rd person singular

It comes from the verb nuncupare.

So it means he/she/it names, declares, or formally designates.
Here, because the subject is testator, it means the testator names or declares.

It is usually more formal than a simple everyday calls.

Nuncupare often has the sense of:

• formally naming
• solemnly declaring
• designating by name

That makes it especially suitable in a legal context like wills and inheritance. In this sentence, it suggests not casual speech, but an official or deliberate declaration.

Classical Latin normally has no articles like English the and a/an.

So a noun such as testator can mean:

• the testator
• a testator

And heredem can mean:

• the heir
• an heir

Which one sounds best depends on the context and the translation choice. English needs an article, but Latin usually does not.

Yes. Latin word order is more flexible than English word order because the endings show the grammatical roles.

This sentence could be rearranged in several ways without changing the basic meaning, for example:

• Testator heredem palam nuncupat
• Testator palam heredem nuncupat
• Heredem testator palam nuncupat

The chosen order is natural and clear:

• testator first introduces the subject,
• heredem gives the object,
• palam adds manner,
• nuncupat comes last, which is very common in Latin prose.

In Latin, you often rely more on case endings than on position.

Here:

• testator is nominative, so it is the subject,
• heredem is accusative, so it is the direct object,
• nuncupat is the verb,
• palam is an adverb.

So even if the order changes, the endings still tell you the structure.

That is one of the biggest differences from English, where word order does much more of the grammatical work.

Yes, in a sense. The verb ending -t in nuncupat already tells you the subject is he/she/it in the singular.

Latin often does not need to state a separate subject pronoun unless it wants emphasis or contrast.

So:

• nuncupat by itself could mean he/she/it names
• with testator, the subject is made explicit: the testator names

Yes. English testator comes directly from Latin testator.

In both languages it refers to a person who makes a will. This is one of those helpful cases where legal English preserves a Latin word with nearly the same meaning.

A very close grammatical breakdown is:

• Testator = the testator
• heredem = an heir / the heir
• palam = openly / publicly
• nuncupat = names / formally declares

So the sentence is literally something like:

The testator openly names an heir.

Depending on context, you could also bring out the formal sense of nuncupat:

The testator publicly declares an heir.