baby talk

Short definition from Wiktionary

Noun

1. 1
   The form of speech used by adults in talking to very young children.
2. 2
   The prelanguage, and subsequent developing language, used by small children, incorporating crying, cooing, and babbling in sequence before the acquisition of adult language capabilities.
3. 3
   Alternative form of baby talk.

Verb

1. 1
   Alternative form of babytalk.