Lambdacism

Lambdacism (from the Greek letter lambda) is a medical condition or speech impediment related to the pronunciation of /l/ or related phonemes.

A common form of lambdacism is lallation, the substitution of /l/ for /ɹ/ in pronunciation. It is a common feature of Japanese and Korean pronunciation of English; it occurs to a lesser extent in Mandarin Chinese and other languages. Substitution of /l/ for /n/ at the beginning of a word or syllable (or the reverse at the end) is also a feature in certain East Asian languages, such as Cantonese and Thai.

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