baby talk
From Longman Dictionary of Contemporary EnglishRelated topics: Colours & sounds, Linguisticsbaby talkˈbaby talk noun [uncountable] CSLsounds or words that babies use when they are learning to talkExamples from the Corpusbaby talk• He had been late talking - was that because I hadn't coo-ed at him and gurgled baby talk?• He listened to me talking to him in baby talk.• I crashed into a babble of baby talk.• It seems that baby talk is a natural response that babies elicit from adults!