Definition of "lallation"

She spoke Aramaic with a lazy lallation, affected by many because it was the natural speech of a class.

1918, Earl Williams, chapter 19, in The Court of Belshazzar: A Romance of the Great Captivity‎, Indianapolis: Bobbs-Merrill, page 199

“Everybody wovs you,” Mary Madelyn said to Melchior.Whenever she pronounced an el it became doubleu. […] Except for her partial lallation she spoke well […]

1982, Bernard Malamud, “The Schooltree”, in God’s Grace

When you talke with your children you expect from them no congruence or quaint language, yet you are often pleased to heare them prattle, & are delighted with their lisping Ideoms. This makes me hope that you will dispence with the Lallation & Low dialect of this babe, whose tone is rude, yet his meaning is plaine dealing, which according to the proverbe is a jewell, and consequently most fit for Ladies.

1648, Robert Baron, Erotopaignion, Or the Cyprian Academy, London: J. Hardesty et al., “To the Ladies and Gentlewoemen of England,”

The auto-imitation in lallation, a form of spontaneous talking, precedes the imitation of strange words and sounds. […] in lallation the infant follows his own inclination, while in imitating the sound heard from others he will have to accommodate himself to a strange perception.

1914, Max Nadoleczny, “Disorders of Speech and Phonation in Childhood”, in Diseases of the Eye and Disorders of Speech in Childhood‎, Philadelphia: J.B. Lippincott, page 362

The chronic effects of the barbiturates on neurological and psychic function resemble those of alcohol. There may be dizziness, clumsiness and ataxia; dysarthria, nystagmus, mental disturbances, nervousness, tremor, lallation, confusion, peculiar behavior, weakness of judgment, emotional instability and hallucinations.

1962, Ashton L. Welsh, Side Effects of Anti-Obesity Drugs‎, Springfield, Illinois: Charles C. Thomas, Part 3, p. 173