| 1 | Middle English | curious | careful, meticulous; ingenious, skilful; expert,... |
| 2 | Old French | curios | — |
| 3 | Latin | curiosus | Careful, diligent, thoughtful, devoted;... |
| 4 | Latin | -osus | -ose, -ous; full of, overly, prone to |
| 5 | Old Latin | -osos | accusative masculine plural of -ōsus |
| 6 | Latin | ont-to-s | — |
| 7 | Latin | -o-wont-to-s | — |