| Nominativ | quartusdecimum, quartusdecima, quartusdecimus | quartusdecima, quartusdecimae, quartusdecimi |
| Genitiv | quartusdecimae, quartusdecimi, quartusdecimi | quartusdecimorum, quartusdecimorum, quartusdecimarum |
| Dativ | quartusdecimo, quartusdecimo, quartusdecimae | quartusdecimis |
| Akkusativ | quartusdecimam, quartusdecimum, quartusdecimum | quartusdecima, quartusdecimos, quartusdecimas |
| Ablativ | quartusdecima, quartusdecimo, quartusdecimo | quartusdecimis |
| Vokativ | quartusdecime, quartusdecimum, quartusdecima | quartusdecimi, quartusdecima, quartusdecimae |
