赤ん坊・赤んぼ・赤んぼう|あかんぼうakanbou[0]heiban (flat)

1. nounbaby; infant
   うちの赤ん坊あかんぼうは口くちをきくようになってきました。↗

   Our baby is learning to speak.

• Synonym赤子あかごWrittenWritten word for a baby; in 「赤子の手をひねる」 it appears in a metaphor for something very easy to do.
• Synonym赤ちゃんあかちゃんNeutralThe everyday, affectionate name for a baby, common in ordinary situations too, as in 「かわいい赤ちゃん」; it sounds softer than 「赤ん坊」.
• Synonym乳児にゅうじWrittenWritten term for a baby under one year old, used mostly in medical contexts, as in 「乳児検診」.
• SynonymベビーCasualCasual loanword for baby; it most often serves as a prefix, as in 「ベビー用品」.
• Synonym幼子おさなごWrittenWritten word for a young child; its range is broader than 「赤ん坊」, taking in little children beyond infancy.
• SynonymみどりごWrittenWritten word for a newborn baby, with a literary, old-fashioned flavor; you will mostly meet it in literature rather than in speech.
• Related乳飲み子ちのみごWrittenWritten word for a baby still at the breast, as in 「乳飲み子を抱えて」.
• RelatedねんねCasualBaby talk for sleeping or bedtime; it can also mean a baby, or an immature young woman.
• Antonym大人おとなNeutralThe opposite of 「赤ん坊」: a grown-up, as in 「大人になる」.
• Antonym老人ろうじんNeutralThe age opposite of 「赤ん坊」: an old person or the elderly.

In everyday speech 「赤ちゃん」 is the usual choice, warm and affectionate; 「赤ん坊」 is also common but a little casual. Use 「乳児」 in medical contexts, 「赤子」 or 「嬰児」 in written prose, and 「ベビー」 as a prefix. The opposites are 「大人」 and 「老人」.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

1. 生うまれて間まもない子供こどもや胎児たいじ。
2. 世間せけん知しらず。