Where does “treinta” come from?

treinta (Old Portuguese) comes from Latin triginta, from Proto-Indo-European tri(d)ḱomt — thirty; three-ten.

Ancestry of “treinta”, step by step

StepLanguageWordMeaning
1Latintrigintathirty; 30
2Proto-Indo-Europeantri(d)ḱomtthirty; three-ten
Every word from Proto-Indo-European tri(d)ḱomt →Every word from Latin triginta →