哺乳類（ほにゅうるい、honyuurui）
- mammal

The Japanese word 哺乳類 (ほにゅうるい) means "mammal." It refers to any animal of the class Mammalia, which is characterized by the presence of mammary glands, hair or fur, and three middle ear bones. These animals are warm-blooded and typically give birth to live young. 哺乳類 encompasses a wide range of creatures, from tiny shrews to enormous whales, all of which share these fundamental characteristics.

⚫︎犬は哺乳類です。 Translation: Dogs are mammals. ⚫︎クジラは哺乳類の中でも最大の動物です。 Translation: Whales are among the largest mammals. ⚫︎コウモリは珍しい哺乳類です。 Translation: Bats are unusual mammals.

You use the word 哺乳類 in situations where you want to talk about mammals in general, or to classify an animal as a mammal. It's used in scientific contexts, everyday conversation, and educational settings. The context will generally be biological or zoological. You would use this word when talking about animal classification, discussing animal characteristics, or learning about animals.

哺乳類 is written using the kanji 哺乳 (meaning "nursing" or "suckling") and the kanji 類 (meaning "class" or "type"). The pronunciation is ほにゅうるい in hiragana. There are no other common ways to write this word. The okurigana is fixed.

There aren't direct synonyms for 哺乳類 in the same way, as it is a specific scientific classification. However, you could use more general terms depending on the context. However there are no exact synonyms. ⚫︎動物 (どうぶつ) - animal (can be used in more general discussions) ⚫︎獣 (けもの) - beast, animal (can be used to refer to four-legged mammals)

The direct antonyms would be the other major classifications of animals. ⚫︎鳥類 (ちょうるい) - birds ⚫︎爬虫類 (はちゅうるい) - reptiles ⚫︎両生類 (りょうせいるい) - amphibians ⚫︎魚類 (ぎょるい) - fish ⚫︎昆虫類 (こんちゅうるい) - insects

世界には様々な種類の哺乳類がいます。 ・Translation: There are various types of mammals in the world. ・Explanation: This sentence discusses the diversity within the mammal class.

パンダは、笹を食べる哺乳類です。 ・Translation: Pandas are mammals that eat bamboo. ・Explanation: This sentence classifies a panda as a mammal and explains its diet.

The word 哺乳類 is a compound word. The first two kanji, 哺乳, combine to refer to the act of "nursing" or "suckling," directly relating to the primary defining characteristic of mammals, which is the production of milk by the mammary glands. The second kanji, 類, indicates a "class" or "type." So, the word literally means "milk-sucking type" or "class of milk-suckling animals," accurately reflecting the biological classification. The combination of 哺乳and 類is the Japanese way to categorize this group of animals.