This is the 14145th most frequent Spanish word.
tongano
Tongano: Tongan; relating to Tonga or its people.
Here, 'tongano' is used as an adjective describing the nationality of the rugby team.
El equipo de rugby tongano participó en el torneo internacional.
The Tongan rugby team participated in the international tournament.
In this sentence, 'tongan(o/a)' is used as an adjective to qualify the word 'cultura' (culture), matching its feminine form.
Aprendí mucho sobre la cultura tongana en mi último viaje.
I learned a lot about Tongan culture on my last trip.
In this context, 'tongano' is used in plural form and as a noun to talk about a person's ethnic background.