| 1 | Ancient Greek | πτῶσις | falling, a fall; case; inflection |
| 2 | Ancient Greek | πίπτω | to fall, throw oneself down |
| 3 | Ancient Greek | -ωσις | abnormal condition or state; state, abnormal... |
| 4 | Ancient Greek | -σῐς | "suffix forming nouns" |
| 5 | Ancient Greek | -τις | Earlier form of -σις , retained after dentals δ,... |
| 6 | Proto-Indo-European | -tis | Derives abstract/action nouns from verb roots |