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lallation

American  
[la-ley-shuhn] / læˈleɪ ʃən /

noun

  1. a speech articulation error or disorder in which l is pronounced instead of r, or in which an l- sound is mispronounced.

  2. the production of speech sounds characteristic of infants around the age of six months, primarily the attempted reproduction and repetition of some syllables perceived in the speech of others.


lallation British  
/ læˈleɪʃən /

noun

  1. phonetics a defect of speech consisting of the pronunciation of (r) as (l)

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of lallation

First recorded in 1640–50; from Latin lallā(re) “to sing lala or a lullaby” + -tion