The story
- Englishennea-
- Proto-Indo-European*déḱm̥
- Proto-Hellenic*dékə
- Ancient Greekδέκᾰ (dékă)
- Ancient Greekδεκάς (dekás)
- Late Latindecas
- Frenchdéca-
- Englishdeca-
- English todayenneadeca-
From ennea- + deca-. Compare Ancient Greek ἐννεακαίδεκα (enneakaídeka).
Etymology from Wiktionary, CC BY-SA 4.0.