| 1 | Ido | radio | ray, beam, gleam; radio; radius |
| 2 | Ido | radiar | to radiate, irradiate; to emit rays or beams; to... |
| 3 | English | radiate | To extend, send or spread out from a center like... |
| 4 | French | radial | — |
| 5 | German | radial | radial; radially |
| 6 | Italian | radiale | radial; radial, radial tire; radial, radius bone |
| 7 | Spanish | radial | radial; of or pertaining to radio; radian |
| 8 | Spanish | radio | radio; radius; radium |
| 9 | French | radium | radium |
| 10 | French | radioactif | radioactive |
| 11 | French | actif | active; asset; top |
| 12 | Old French | actif | active |
| 13 | Latin | āctīvus | — |
| 14 | Latin | agō | — |
| 15 | Proto-Italic | agō | drive; push, impel; do, act |
| 16 | Proto-Indo-European | h₂éǵeti | to be driving |
| 17 | Proto-Indo-European | h₂eǵ- | to drive |