see: iwi'iwi'
The relationship between *Iwi'iwi'* and *Wi'wi'* is that *Iwi'iwi'* describes a facial expression that could include the lip disfiguration described by *Wi'wi'*. The repetition in ”Iwi'iwi' “ intensify or emphasize the emotional state, while *Wi'wi'* specifically highlights the physical aspect of the lip's appearance.