Understanding the Meaning of だ (da) and です (desu) in Japanese

The copula だ is at the center of the Japanese language and grammar. だ is a notoriously complicated grammatical construct, but it's also an essential part of understanding a sentence in Japanese.

Whether you're just starting out in your Japanese language journey or you're a seasoned learner, understanding the ins and outs of だ is crucial for clear communication.

In this post, we'll take a deep dive into the world of だ, exploring its meaning, usage, and conjugation rules.

What does だ mean in Japanese

The verb だ／です (da / desu) means to be, is, or are. だ is the copula in Japanese and it is one of the first elements that one learns at the beginning of the study of the language.

The plain form we find in the dictionary is だ and its polite form である.

です is often considered a polite form of だ; it actually belongs to Sonkeigo 尊(そん)敬(けい)語(ご), the honorific language of respect.

Let's see the meaning of だ taken from an original Japanese dictionary:

In the definition we see the term 断(だん)定(てい)する, which means conclusion, statement, affirmative. だ is generally used at the end of a sentence to affirm and emphasize what said.

Grammar rules for だ in Japanese

だ／です is placed as for all verbs at the end of the sentence and follows nouns and adjectives.

Adjectives ending in な behave like nouns.

The plain form だ is not used with adjectives ending in い.

With adjectives ending in い you can use です instead.

だ and です can be followed by exclamation particles よ and ね.

How to use だ in Japanese

だ／です is an auxiliary verb and is used to determine and state something. It expresses that a thing, person or situation is a certain way.

だ／です are also defined verb to be of identification, compared to the verbs ある and いる which instead translate the verb to be of existence (there is, there are).

Using だ in interrogative form: ですか and なの

The interrogative form is obtained with:

• です polite form and the interrogative particle か
• な instead of だ and の as an interrogative particle, generally only in a confidential and informal context

Expressions using だ in Japanese

The copula だ is part of many expressions which are also very useful and used in the Japanese language.

だ is often found after a noun at the end of a sentence. An example is the expression つもりだ:

The term つもり indicates an intention or plan. When だ follows つもり the expression indicates the intention is.

Let's see an example:

Using だ at the end of the sentence adds a lot of emphasis and makes the sentence direct and strong. To make the sentence less direct, the polite form です can be used.

Another example is the expression とおりだ:

Combining the copula だ with the particle よ at the end of the sentence adds extra emphasis.

Usage of だ in Japanese: examples and translations