babytalk

/B AE0 B AH0 T AO0 K/
noun
  1. 1

    The form of speech used by adults in talking to very young children.

verb
  1. 1

    To speak in baby talk (form of speech used by adults in talking to very young children).

Source: https://en.wiktionary.org/wiki/baby%20talk, https://en.wiktionary.org/wiki/babytalk