Japanese Family Members Vocabulary: Haha or Okāsan? Who Says What

The rule: whose family, and who is listening

Japanese draws a line between inside and outside. Your own family is inside, and when you talk about them to an outsider, such as a teacher, a coworker or a new acquaintance, you use plain, modest words: 母 (haha), 父 (chichi). Other people's families are outside, and you use polite words with お〜さん: お母さん (okāsan), お父さん (otōsan).

The twist is that inside the family, people often call each other with the polite set. A child calls out okāsan! in the kitchen, and a mother may say okāsan about herself when talking to her children. So the polite word has two jobs: someone else's mother, and Mum.

Mother and father: four words to start with

Among friends, many adults also say uchi no okan or uchi no oyaji, casual and slightly rough words for mum and dad, or simply okāsan about their own mother. That is fine with close friends, but at work or in an interview, haha and chichi are expected. Calling your own mother okāsan in a job interview is a classic slip that interviewers notice.

Grandparents, aunts, uncles and cousins

The same inside and outside rule applies to the wider family. The plain words, sofu and sobo, sound quite formal, so in casual talk many people say uchi no ojīchan or uchi no obāchan even about their own grandparents.

Be careful with the long vowels: おじいさん (ojīsan) is grandfather, but おじさん (ojisan) is uncle or a middle-aged man; おばあさん (obāsan) is grandmother, but おばさん (obasan) is aunt or a middle-aged woman. In writing, uncle and aunt have two kanji each, depending on whether they are older or younger than your parent: 伯父 and 叔父 for uncle, 伯母 and 叔母 for aunt. In speech, both are simply oji and oba.

Brothers and sisters: older and younger

Japanese has no single word for brother or sister. You always say whether the sibling is older or younger. At home, older siblings are usually called by a title, onīchan or onēchan, while younger siblings are called by their name. This reflects the importance of age order in many Japanese families, though plenty of siblings simply use names or nicknames.

Husbands, wives and children

Spouse words are where Japanese is changing fastest. Traditional words such as 主人 (shujin, literally master) for your own husband and 家内 (kanai, literally inside the house) for your own wife are still used, especially by older people, but many people now prefer the neutral 夫 (otto) and 妻 (tsuma). 嫁 (yome), literally bride or daughter-in-law, is widely used casually for one's own wife, especially in western Japan, but some people dislike it. When in doubt, choose otto and tsuma.

Okosan wa nansai desu ka, how old is your child, is a very common small-talk question for parents. Your own children are simply kodomo: Kodomo ga futari imasu, I have two children.

In-laws and blended families

For in-laws, Japanese adds 義理の (giri no), in-law or by marriage, or the prefix 義 (gi). The same words are used for step-relatives. In conversation, many people call their spouse's parents okāsan and otōsan directly, the same as their own parents, which surprises some learners at first.

実家 (jikka) is your family home, where your parents live. It is a key word around holidays such as New Year and Obon, when many people go back to their own jikka or their spouse's.

Mini dialogues: at work and at a friend's home

In the first dialogue, you talk about your family to a coworker. In the second, you meet a friend's family, and the words for the same people change.

Notice that the friend's mother calls your mother okāsan, because to her, your mother is outside her family. You keep saying haha. Between friends of the same age, you would call your friend's grandmother obāchan if the family does, and her parents okāsan and otōsan, or with the family name: Tanaka-san no okāsan.

Drill the switch with Mocchi

Ask Mocchi: Give me ten situations and make me choose between haha, okāsan and mama. Mocchi sets up a coworker, a friend's parent or a phone call home, tells you why each answer fits, and keeps track of the switches you get wrong, so they show up again in your next /review. When you are ready, use /kaiwa and Mocchi will suggest a family roleplay for AI Sensei. Hana-sensei can play your friend's mother welcoming you home, and the session report shows every time you slipped into the wrong set.

Common learner mistakes

• Saying watashi no okāsan to a teacher or coworker. Use haha.
• Calling a friend's mother anata no haha. Say okāsan, or Tanaka-san no okāsan.
• Mixing ojisan (uncle, middle-aged man) and ojīsan (grandfather, old man). The long vowel changes the meaning.
• Asking burazā wa imasu ka. Use kyōdai wa imasu ka, and say older or younger in the answer.
• Using omae or anata to address your parents. Japanese family members address each other by role or name.