A phonological process in Japanese. The word means ˈsequential voicing”. The initial consonant of the second element of a compound word is changed from voiceless to voiced. An example is the well-known Japanese word origami (paper folding). The elements of this compound are ori (“fold”) and kami (“paper”). The process has many exceptions and is subject to many conditions. The most general constraint on the operation of rendaku is known as Lyman’s law. If the second element of a compound contains a voiced obstruent, then rendaku does not apply. For example, hitori+tabi (“one person”+”travelling”) gives hitoritabi not hitoridabi, because of the b in the second element.