| Singular | Plural | |
|---|---|---|
| Nominativ | dubium | dubiatis, haudubia, dubia |
| Genitiv | dubiaeque, dubiose, dubiosus, dubitantus, dubitemne, dubii, mandubii, dubi | dubiorum, mandubiorum |
| Dativ | dubio, dubioque | dubiis, dubiisque, mandubiis |
| Akkusativ | dubium | dubiatis, haudubia, dubia |
| Ablativ | dubio, dubioque | dubiis, dubiisque, mandubiis |
| Vokativ | dubium | dubiatis, haudubia, dubia |