| Singular | Plural | |
|---|---|---|
| Nominativ | archidiaconus | archidiaconi |
| Genitiv | archidiaconi | archidiaconorum, archidiaconum |
| Dativ | archidiacono | archidiaconis |
| Akkusativ | archidiaconom, archidiaconum | archidiaconos |
| Ablativ | archidiacono | archidiaconis |
| Vokativ | archidiacone | archidiaconi |