laˈlāshən noun
( -s )
Etymology: Latin lallare to sing a lullaby + English -tion — more at -lalia
1. : infantile utterance whether in infants or in older speakers (as by retardation or mimicry)
2. : a defective articulation of the letter l , the substitution of l for another sound, or the substitution of another sound for l — compare lambdacism