Demetrius, of Greek origin, means 'belonging to Demeter', the goddess of agriculture and fertility in Greek mythology. This name was quite popular among ancient Greeks but has since become less common. It is composed of two elements: 'demos' meaning 'people' and 'etere' which signifies 'to nourish'. Thus, Demetrius could be interpreted as 'nourisher of the people'. The name gained prominence during Roman times and was often associated with powerful figures such as Demetrius Poliorcetes ('the Besieger'), a king from Macedonia who lived in the 3rd century BCE. Today, it is still used sporadically around the world, particularly in countries with historic ties to ancient Greece or the Roman Empire.
The name Demetirus was only given to six children worldwide during the year 1987.