Mater dolorem occultum in vultu filiae videt.

Here is the basic grammar of each word:

• Mater = mother; nominative singular, so it is the subject
• dolorem = pain; accusative singular, so it is the direct object
• occultum = hidden / concealed; accusative singular masculine, agreeing with dolorem
• in vultu = in the face / on the face / in the expression
• filiae = of the daughter; genitive singular
• videt = sees; 3rd person singular present active

So structurally, the sentence is:

Mother sees hidden pain in the daughter’s face.

Because mater is in the nominative case, which is the case usually used for the subject of a finite verb in Latin.

Also, videt means he/she/it sees, so it needs a singular subject. Mater fits perfectly: the mother sees.

Because it is the direct object of videt.

In Latin, the thing that is directly seen, heard, loved, feared, and so on is usually put in the accusative case. Here, what does the mother see? She sees dolorem occultum.

So:

• videt = sees
• dolorem = the thing seen

That is why dolorem is accusative singular.

Because occultum must agree with the noun it describes, and it describes dolorem.

Dolorem is:

• masculine
• singular
• accusative

So the adjective must also be:

• masculine
• singular
• accusative

That gives occultum.

If the noun were nominative singular, then occultus would be possible. But here the noun is accusative, so occultum is required.

In Latin, adjectives agree with the nouns they modify in gender, number, and case.

• dolorem = masculine singular accusative
• occultum = masculine singular accusative

That match shows they belong together.

By contrast:

• mater is nominative singular
• vultu is ablative singular
• filiae is genitive singular

So occultum cannot be modifying those words.

Yes, this is a good example of a fourth-declension form.

Vultus, vultus is a fourth-declension masculine noun meaning face, expression, or countenance. Its ablative singular is vultu.

It is ablative here because it follows in in the sense of in / on a place or visible location:

• in vultu = in the face, on the face, in the expression

With in, Latin usually uses:

• ablative for location: in the face
• accusative for motion into: into the face would be very different

Here there is no motion, only location, so ablative is correct.

The form filiae can have several possible grammatical functions in Latin, but here the context clearly makes it genitive singular.

It goes with vultu:

• vultu filiae = the daughter’s face or the face of the daughter

So filiae answers the question whose face?

That is exactly what the genitive does.

Although filiae can also be dative singular or nominative plural in other contexts, those meanings do not fit this sentence nearly as well.

Because Latin does not have articles like English the and a/an.

So a word like mater can mean:

• mother
• a mother
• the mother

The exact sense depends on context.

The same is true for dolorem, vultu, and filiae. English usually has to add articles when translating, but Latin does not need them.

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

English depends heavily on order:

• The mother sees the pain

If you rearrange that in English, the meaning may change or become unclear.

Latin can move words around more freely because the cases tell you what each word is doing:

• mater = subject
• dolorem = object
• vultu = ablative phrase
• filiae = genitive dependent on vultu

So Mater dolorem occultum in vultu filiae videt is perfectly normal Latin. Putting videt at the end is especially common.

Yes, in many cases.

For example, these would still mean essentially the same thing:

• Mater in vultu filiae dolorem occultum videt.
• Dolorem occultum mater in vultu filiae videt.
• In vultu filiae mater dolorem occultum videt.

The endings still show the grammar.

That said, word order in Latin is not meaningless. Different arrangements can shift emphasis or focus. For example:

• starting with mater highlights the mother
• starting with dolorem occultum highlights the hidden pain
• starting with in vultu filiae highlights where the mother notices it

Literally, yes, in vultu means in the face. But in natural English, it often means something like:

• on the daughter’s face
• in her expression
• in her countenance

Latin vultus often refers not just to the physical face, but also to the look or expression shown on it. So the idea is that the mother notices the hidden pain from the daughter’s facial expression.

Videt is:

• present tense
• 3rd person singular
• active voice

So it means he/she/it sees.

Because the subject is mater, the full sense is the mother sees.

If you compare:

• video = I see
• vides = you see
• videt = he/she/it sees

then videt is the expected form here.

Not necessarily invisible in an absolute sense. Occultus means hidden, concealed, or not openly shown.

So the idea is that the daughter is not directly stating or openly displaying her pain, but the mother can still perceive it in her face.

In other words, the pain is hidden, yet still detectable to someone observant. That is a very natural idea in both Latin and English.