LATIN DICTIONARYLexicon Latīnum
adverb

tertium

tertium (not comparable)
Classical[ˈtɛr.ti.ũː]Ecclesiastical[ˈtɛr.t͡si.um]

Meaning

  1. not comparablefor the third time

tertĭum, adv., v. tertius, B.
I. fin.

Origins

Adverbial accusative of tertius.

Quick answers

What does tertium mean in Latin?
tertium, a adverb, means “for the third time”.
How do you pronounce tertium?
In classical Latin, [ˈtɛr.ti.ũː]; in ecclesiastical (church) Latin, [ˈtɛr.t͡si.um].