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Metathesis (Gr. μετάθεσις) is the transposition of sounds or letters in a word, commonly precipitated by a slip of the ear or of the pen. As a linguistic process, metathesis has changed the written form and pronunciation of many words. For example, bird is a metathesized metathesised form of OE bryd. Usually the phenomenon refers to contiguous sounds which is called adjacent metathesis. Metathesis may also describe the transposition of non-adjacent sounds and/or letters as in Spanish palabra from Latin parabola. Cf. types of errors.
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