What does septimusdecimus mean in Latin?

septimusdecimus, a numeral, means “seventeenth”.

How do you pronounce septimusdecimus?

In classical Latin, [sɛp.tɪ.mʊsˈdɛ.kɪ.mʊs]; in ecclesiastical (church) Latin, [sep.ti.muzˈdɛː.t͡ʃi.mus].

numeralfirst/second-declension numeral with a first/second-declension numeral

septimusdecimus (feminine septimadecima, neuter septimumdecimum)

Classical[sɛp.tɪ.mʊsˈdɛ.kɪ.mʊs]Ecclesiastical[sep.ti.muzˈdɛː.t͡ʃi.mus]

singular
form	masculine	feminine	neuter
nominative	septimusdecimus	septimadecima	septimumdecimum
genitive	septimīdecimī	septimaedecimae	septimīdecimī
dative	septimōdecimō	septimaedecimae	septimōdecimō
accusative	septimumdecimum	septimamdecimam	septimumdecimum
ablative	septimōdecimō	septimādecimā	septimōdecimō
vocative	septimedecime	septimadecima	septimumdecimum

plural
form	masculine	feminine	neuter
nominative	septimīdecimī	septimaedecimae	septimadecima
genitive	septimōrumdecimōrum	septimārumdecimārum	septimōrumdecimōrum
dative	septimīsdecimīs	septimīsdecimīs	septimīsdecimīs
accusative	septimōsdecimōs	septimāsdecimās	septimadecima
ablative	septimīsdecimīs	septimīsdecimīs	septimīsdecimīs
vocative	septimīdecimī	septimaedecimae	septimadecima

septĭmusdĕcĭmus, a, um, v. septimus, I.

Proto-Italic *dekəmos Latin decimus Latin septimusdecimus From septimus (“seventh”) + decimus (“tenth”).