iwituaroa
1. (noun) backbone, spinal column, spine (of the body) - sometimes written as two words, i.e. iwi tuaroa.
Takahia ana e Māui te iwituaroa, kūmea ana te whiore; ka whakakurītia e Māui a Irawaru (NM 1928:20). / Māui trampled on the backbone and pulled out the tail, turning Irawaru into a dog.