Definition of lallation in English:

lallation

noun

mass noun
  • 1Imperfect speech, especially the repetition of meaningless sounds by babies.

    1. 1.1 The pronunciation of r as l.

Origin

Mid 17th century: from Latin lallatio(n-), from lallare ‘sing a lullaby’.

Pronunciation

lallation

/laˈleɪʃ(ə)n/