langage A French term introduced by Ferdinand de Saussure to refer to the human biological faculty of speech. It is distinguished in his approach from langue, the language system of a speech community.
listeme A term occasionally used in psycholinguistics for the notion of a word or other expression as a member of a list of linguistic entities stored in the brain.
ludic A term sometimes used in linguistics to refer to language whose primary function is to be part of play, as in the nonsense, repetitive rhythms and rhymes heard in children's games all over the world. Ludicity also affects adults, who may play with language by adopting silly tones of voice or by twisting words into unorthodox shapes to create a humorous effect.
Definitions from: A Dictionary of Linguistics and Phonetics, Sixth edition, 2008
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