Tongan ua

← Proto-Austronesian *duSa (inherited)

← Proto-Central-Eastern Malayo-Polynesian *dua (inherited)

← Proto-Oceanic *rua (inherited)

← Proto-Polynesian *rua (inherited)

← Proto-Malayo-Polynesian *duha (inherited)

← Proto-Eastern Malayo-Polynesian *dua (inherited)

→ Tongan uofulu (mention)