Банкомат сірий.

In Ukrainian, the verb to be is usually omitted in the present tense.

So:

• Банкомат сірий. = The ATM is gray.

You do not normally say Банкомат є сірий in a basic sentence like this.

A useful comparison:

• Банкомат сірий. = The ATM is gray.
• Банкомат був сірий. = The ATM was gray.
• Банкомат буде сірий. = The ATM will be gray.

So the missing is is completely normal.

Here сірий is part of the predicate, not just a noun modifier.

• Банкомат сірий. literally means The ATM is gray.
• Сірий банкомат. means a/the gray ATM

So:

• before the noun = adjective directly describes the noun
• after the noun = often part of the statement about the noun

This is similar to the difference between:

• the gray ATM
• the ATM is gray

They are both in the nominative singular masculine.

Why?

• банкомат is the subject of the sentence
• сірий is a predicate adjective agreeing with it

So the adjective matches the noun in:

• gender: masculine
• number: singular
• case: nominative

That is why you see:

• банкомат
  • сірий

The ending -ий is the normal masculine singular nominative ending for many adjectives.

Since банкомат is:

• masculine
• singular
• nominative

the adjective must agree with it:

• сірий = masculine singular nominative

Compare:

• банкомат сірий = masculine
• машина сіра = feminine
• вікно сіре = neuter
• банкомати сірі = plural

So the adjective ending changes depending on the noun.

A very common clue in Ukrainian is the noun ending.

Банкомат ends in a consonant, and nouns ending in a consonant are often masculine.

So:

• банкомат → masculine

That is why it pairs with masculine adjective forms like:

• сірий

This rule is not absolutely universal for every noun in the language, but it is a very reliable pattern.

It can mean either, depending on context, because Ukrainian has no articles like a or the.

So банкомат by itself can be understood as:

• an ATM
• the ATM

In practice, context tells you which one is meant.

For example:

• if you are pointing at a specific machine, it probably means the ATM
• if you are speaking more generally, it could be an ATM

A rough pronunciation guide is:

• банкомат ≈ banko-MAHT
• сірий ≈ SEE-riy

A rough transliteration:

• Bankomat siryi

Stress:

• банкома́т
• сі́рий

A few sound notes:

• і sounds like ee in see
• и is not the same as English ee; it is a shorter, more central sound
• г does not appear here, so you do not need to worry about it in this sentence

It is a standard Ukrainian word, but it is a relatively modern international-type word, similar to English ATM.

Ukrainian commonly uses:

• банкомат = ATM / cash machine

So even though English usually says ATM, Ukrainian normally says банкомат in everyday speech.

Yes. That means This ATM is gray.

Compare:

• Банкомат сірий. = The ATM is gray / An ATM is gray
• Цей банкомат сірий. = This ATM is gray

Adding цей makes the noun specific.

Because банкомат is masculine singular, you use:

• цей for this

Yes, but then the structure and emphasis change.

Compare:

• Сірий банкомат. = The gray ATM / A gray ATM
  This is a noun phrase, not usually a complete sentence by itself.
• Сірий банкомат стоїть біля входу. = The gray ATM stands/is located near the entrance.
• Банкомат сірий. = The ATM is gray.

So in your sentence, the adjective comes after the noun because it is saying something about the ATM, not just naming it.

Yes. Банкомат сірий. is a complete, natural, simple Ukrainian sentence.

It has:

• a subject: банкомат
• a predicate adjective: сірий

Even without a present-tense verb, it is fully grammatical in Ukrainian.

It is a very typical beginner-style pattern:

• X + adjective

For example:

• Будинок великий. = The house is big.
• Сік холодний. = The juice is cold.
• Банкомат сірий. = The ATM is gray.