- t-ayra is the converse of the English word father; while the converse of mother is membyra. These two words have the same translations, but could never be used as synonyms in Classical Tupi.
- The stem ayra could never be used inside a sentence without a prefix. The absolute form t-ayra was used whenever the noun was not possessed.
- LEMOS BARBOSA, A. Curso de Tupi antigo. Rio de Janeiro: Livraria São José, 1956.