Translation guide
The English word "baby" covers a wide range of meanings, from a very young child to terms of endearment and slang. This guide breaks down the most useful Japanese equivalents for English-speaking learners, organized by intended meaning.
Referring to a human baby, from newborn to around 2 years old.
The most common and affectionate word for a baby. Safe to use in almost any context.
The baby is crying.
She is holding a baby.
Also means baby, but slightly more matter-of-fact or literary than 赤ちゃん. Often used in written descriptions.
Taking care of a baby is tough.
Formal/medical term for an infant (under 1 year old). Used in official documents or healthcare contexts.
The infant mortality rate is declining.
Referring to a baby still in the womb.
Calling a romantic partner "baby" as a pet name.
Japanese doesn't have a direct equivalent of "baby" as a romantic pet name. Instead, use the person's name with an affectionate suffix like ちゃん (for girls/women or cute nicknames) or くん (for boys/men), or create a nickname. Direct translation would sound very strange.
Never translate "baby" literally as 赤ちゃん for a romantic partner; it would be interpreted as an actual infant.
I love you, baby. (to a girlfriend named Mai)
Come here, baby. (to a boyfriend named Takeru)
Loanword from "darling". Used by some couples, but can sound cheesy or old-fashioned. More common in media than real life.
Calling someone the "baby" of a family, team, etc.
Calling someone a "baby" because they are acting childish.
Referring to a project or idea as one's "baby".
Literally "like one's own child". The most natural way to express this metaphor in Japanese.
This project is my baby.
Means "one's other self" or "alter ego". Can be used for a creation that embodies oneself, but less common for casual projects.
Calling a partner 赤ちゃん (baby) will be understood as referring to an actual infant, not as a term of endearment. Use their name with an affectionate suffix instead.
Hey, baby. (to Yuko)
Both mean "baby," but 赤ちゃん is warmer and more common in speech. 赤ん坊 is slightly more detached and often appears in writing or formal descriptions. For everyday use, stick with 赤ちゃん.
Don't be such a baby!
Expresses childish behavior.
This car is my baby.
Metaphorical use; avoid literal 赤ちゃん.
The fetus is developing normally.
ダーリン、今日は早く帰ってきてね。
Darling, come home early today.
He's like the baby of the team.
He's the baby among his siblings.
His attitude is so babyish.
この作品は私の分身だ。
This work is my baby.