What is a sound formed in the throat; esp., a sound formed by the aid of the back of the tongue, much retracted, and the soft palate; also, a letter representing such a sound called?

guttural — A sound formed in the throat; esp., a sound formed by the aid of the back of the tongue, much retracted, and the soft palate; also, a letter representing such a sound. (Webster's 1913.)

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