interjection, adverb
goo-goo ga-ga; baby babble
Onomatopoeic or mimetic word representing the babbling sound of a baby. Used as an interjection or adverb to describe baby-like speech or behavior.
赤ちゃんが「バブー」と言った。
The baby said 'goo-goo ga-ga'.
彼はバブーと甘えた声を出した。
He made a babyish 'baboo' sound.