What does “iruka” mean in Japanese?
Native speakers say “iruka” to mean ‘dolphin’ in Japanese. Perhaps, some Japanese learners know this word as it is sometimes used in Japanese movies, songs, novels, manga, anime, and the like. In this blog post, however, I will explain it in detail based on its kanji expression. And also, I will explain how to use it through example sentences. My explanations would help Japanese learners understand “iruka” more clearly. Then, let’s get started!
Contents
Definition and meaning of “iruka”
Let me start with the definition and meaning of “iruka”.
- iruka – 海豚 (いるか) : a noun meaning ‘dolphin’ in Japanese. This can also work as plural. Learn more about Japanese plural.
The definition and meaning are simple and clear, I think. To understand this noun more clearly, however, let me explain its kanji characters in detail, one by one.
Iruka in kanji
The kanji expression of “iruka” consists of the following two kanji characters:
- 海 : a kanji character used to mean ‘sea’ or ‘ocean’ in Japanese.
- 豚 : a kanji character used to mean ‘pig’ in Japanese.
These two kanji characters tell us that “iruka” literally means a ‘sea pig’ in Japanese. This literal interpretation is not in line with the actual meaning, but still understandable, I think. Dolphins are mammals like pigs and often live in the sea. So, the kanji expression is not far away from what dolphins really are, or rather it is a good invention based on observations. Unfortunately, however, Japanese native speakers often use the hiragana expression instead of the kanji.

When we meet new kanji expressions, we should check their kanji characters in detail to understand their meanings clearly and deeply. In many cases, kanji characters tell us a lot about the meanings of the expressions they form. Actually, here, we could get the better understanding of “iruka” through the detailed kanji check above.
So far, I’ve explained the definition and meaning of “iruka” together with its kanji characters. Then, let me explain how to use it through the example sentences below.
Example #1: how to say “dolphin” in Japanese
watashi wa kinou iruka wo mi ta – 私は昨日海豚を見た (わたしはきのういるかをみた)
I saw a dolphin yesterday.
Below are the new words used in the example sentence.
- watashi – 私 (わたし) : a pronoun meaning ‘I’ in Japanese.
- wa – は : a bindning particle working as a case marker or topic marker. In the example, this works after “watashi” to make the subject in the sentence.
- kinou – 昨日 (きのう) : a noun meaning ‘yesterday’ in Japanese. This can also work as an adverb almost anywhere in a sentence. In the example, this works as an adverb to say “yesterday” in Japanese.
- wo – を : a case particle used to make the object word in a sentence. In the example, this is used after “iruka” to make the object in the sentence.
- mi – 見 (み) : one conjugation of the verb, “miru“, which means ‘to see’ or such in Japanese. In the example, it has been conjugated for the better connection with its following word.
- ta – た : an auxiliary verb used after a verb, adjective, or auxiliary verb to make its past tense form. Probably, this is well known as a part of Japanese ta form. In the example, this is used after “mi” to make its past tense form, “mi ta”.
This is a typical usage of “iruka”. In the example, it works as the object in the sentence. When we want to say “dolphin” in Japanese, anyway, this noun is a very good option.
Example #2: another usage of “iruka”
iruka wa kujira yori chiisai – 海豚は鯨より小さい (いるかはくじらよりちいさい)
Dolphins are smaller than whales.
Below are the new words used in the example sentence.
- kujira – 鯨 (くじら) : a noun meaning ‘whale’ in Japanese. This can also work as plural.
- yori – より : a case particle working as a comparison marker. In the example, this works after “kujira” to indicate the object which the dolphins are compared with.
- chiisai – 小さい (ちいさい) : an i-adjective meaning ‘small’ in Japanese.
This is another typical usage of “iruka”. In this example, it works as plural to say “dolphins” in Japanese.
Summary
In this blog post, I’ve explained the definition and meaning of “iruka” in detail based on its kanji expression. And also, I’ve explained how to use it through the example sentences. Let me summarize them as follows.
- iruka – 海豚 (いるか) : a noun meaning ‘dolphin’ in Japanese. This can also work as plural. These two kanji characters mean ‘sea’ and ‘pig’ respectively, so this noun literally means a ‘sea pig’ in Japanese. This literal interpretation is not in line with the actual meaning, but still understandable, I think. Dolphins are mammals like pigs and often live in the sea. So, the kanji expression is not far away from what dolphins really are, or rather it is a good invention based on observations. Unfortunately, however, Japanese native speakers often use the hiragana expression instead of the kanji.
Hope my explanations are understandable and helpful for Japanese learners.