lallation
/ˌlælɪˈleɪʃən/Definitions
1. noun
the act of making a high-pitched sound, especially a baby’s cooing or a sound of endearment
“The mother’s lallation was a soothing sound to the fussy infant.”
2. noun
a high-pitched sound, especially a baby’s cooing or a sound of endearment
“The lallation of the baby filled the entire house.”