| Singular | Plural | |
|---|---|---|
| Nominativ | tonitrus | tonitrus, tonitruus |
| Genitiv | tonitri, tonitrus, tonitros | tonitruum, tonitrum |
| Dativ | tonitru, tonitrui, tonitruque | tonitribus, tonitribusque, tonitrubus |
| Akkusativ | tonitrum | tonitrus, tonitruus |
| Ablativ | tonitruque, tonitru | tonitribus, tonitribusque, tonitrubus |
| Vokativ | tonitrus | tonitrus, tonitruus |