An infant or baby; a term for a very young child. Often used interchangeably with '赤ちゃん' and has variant spellings.
赤ん坊の肌はとても柔らかい。
A baby's skin is very soft.
迷子の赤ん坊を見つけたので係員に知らせた。
I found a lost baby and informed the staff.
赤ん坊が初めて笑った瞬間を写真に撮った。
I took a photo of the moment the baby smiled for the first time.