Latin word justus comes from Proto-Indo-European *h₂ey-, Proto-Italic - tos, and later Proto-Indo-European *h₂óyu (Long time, lifetime.)
| Dictionary entry | Language | Definition |
|---|---|---|
| *h₂ey- | Proto-Indo-European (ine) | |
| - tos | Proto-Italic (itc-pro) | |
| *h₂óyu | Proto-Indo-European (ine) | Long time, lifetime. |
| *h₂yew- | Proto-Indo-European (ine) | |
| *h₂yew-es-tos | Proto-Indo-European (ine) | |
| *h₂yéw-os | Proto-Indo-European (ine) | |
| *jowos | Proto-Italic (itc-pro) | Law. Oath. |
| *jowezāō | Proto-Italic (itc-pro) | Swear (an oath). |
| ious | Old Latin (itc-ola) | |
| iuro | Latin (lat) | I swear on oath; I vow. |
| *jowestos | Proto-Italic (itc-pro) | Just, lawful. |
| xurar | Asturian (ast) | To swear (promise). |
| ius | Latin (lat) | Court of law. Law, right, duty. |
| justus | Latin (lat) |