1. (verb) to be big, large, important, major.
He wahine i whai kupu ki ngā take katoa, ahakoa itiiti, ahakoa nunui (TTR 1990:20). / She was a woman who spoke on all matters, whether minor or major.
2. (modifier) large, big - mainly used as the plural form of nui.
I tōna wā ka tū ko ia hei rangatira mō Ngāti Rangiwewehi, tētehi o ngā hapū nunui o Te Arawa (TTR 1990:9). / In his time he became a leader of Ngāti Rangiwewehi, one of the large Te Arawa sub-tribes.
See also nui
3. (noun) size, bigness.
Nō te makurutanga, te nunui o te kūmara (HP 1991:14). / Because of the fertility the kūmara were huge.
(Te Pihinga Textbook (Ed. 2): 44;)