Gladius aciem habet.

Because gladius is in the nominative singular, which is the case normally used for the subject in Latin.

• gladius = sword
• nominative singular = the sword / a sword as the thing doing the action

So in Gladius aciem habet, the sword is the thing that has something.

Because aciem is the accusative singular form of acies.

The noun is:

• acies = nominative singular
• aciem = accusative singular

Latin uses the accusative case for a direct object, and here the direct object is edge. The sword has the edge, so acies changes to aciem.

Aciem is in the accusative singular.

It is accusative because it is the direct object of habet (has). A good way to test this in English is to ask:

• The sword has what?
• It has an edge

That makes edge the direct object, so Latin uses the accusative: aciem.

Habet is:

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

It comes from the verb habeo, habere = to have.

So habet means he/she/it has. Since gladius is singular, the verb is singular too: the sword has.

Latin usually has no articles like English the or a/an.

So gladius can mean:

• the sword
• a sword

And aciem can mean:

• the edge
• an edge

You figure out which is best from the context. That is very normal in Latin.

It can mean either one, depending on context.

Because Latin has no articles, the sentence may be understood as:

• The sword has an edge
• A sword has an edge
• Sometimes even a more general idea like A sword is a thing with an edge

The surrounding context tells you which reading is most natural.

Yes. Latin word order is more flexible than English word order because the endings show each word’s job.

So these could all express the same basic idea:

• Gladius aciem habet
• Aciem gladius habet
• Gladius habet aciem

The most neutral order here is probably Gladius aciem habet, but changing the order can change emphasis.

They are:

• gladius, gladii (masculine) = sword
• acies, aciei (feminine) = edge, sharp edge, and in other contexts battle line
• habeo, habere, habui, habitum = to have

Latin dictionaries usually list nouns in the nominative singular + genitive singular, and verbs in their main principal parts.

• gladius is a 2nd-declension masculine noun
• acies is a 5th-declension feminine noun

That matters because each declension has its own pattern of endings.

For example:

gladius

• nominative singular: gladius

acies

• nominative singular: acies
• accusative singular: aciem

So in this sentence, the endings help show who is doing the action and what is being acted on.

Because it is not the direct object. It is the subject.

In Latin:

• subject → usually nominative
• direct object → usually accusative

So:

• gladius = nominative subject
• aciem = accusative object

If both were accusative, the sentence would not clearly show which noun is the subject.

Yes, but it is a word with a range of meanings. Acies can mean:

• edge
• sharp edge
• point
• battle line or line of battle, depending on context

In this sentence, because of gladius (sword), the meaning edge is the natural one.

A common Classical pronunciation would be roughly:

• gladius = GLAH-dee-oos
• aciem = AH-kee-em
• habet = HAH-bet

A few helpful points:

• g is always hard, as in go
• c is always hard, as in cat
• v in Classical Latin sounds like w, though there is no v in this sentence

So the whole sentence is roughly:

GLAH-dee-oos AH-kee-em HAH-bet

Yes, very often. Latin can omit a subject pronoun because the verb ending already gives information about the subject.

For example:

• habet by itself means he/she/it has

But in this sentence, gladius is included because we need to know what has the edge.

It follows a very common Latin pattern:

Subject + Direct Object + Verb

So here:

• Gladius = subject
• aciem = direct object
• habet = verb

This is a simple and useful beginner pattern, even though Latin can vary the order more than English.