Definition - That which is a surface form. As opposed to emic, which denotes the underlying form.

For example, phonemes are emic because they are our underlying mental representation of our language's sounds, whereas phones are etic because they are the surface (or physical) sounds that are produced when we speak.

Etymology -
According to the Wikipedia, the linguist Kenneth Pike coined both terms in 1954 by contracting phonemic and phonetic.

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