| 1 | Latin | scepticus | The sect of skeptics |
| 2 | Ancient Greek | σκεπτικός | thoughtful, inquiring; a sceptic, a member of the... |
| 3 | Ancient Greek | σκέπτομαι | I look at, examine; I examine, consider, think |
| 4 | Proto-Hellenic | sképťomai | to look at |
| 5 | Proto-Indo-European | spéḱyeti | to be looking at, to keep looking at |
| 6 | Proto-Indo-European | speḱ- | to see, to look, to observe |