Definition from Wiktionary, the free dictionary
Etymology 1 
Abbreviated form of demonstration.
- Plural of demo.
Etymology 2 
From Ancient Greek δῆμος (demos, “the people”).
demos (plural demoi)
- (political science) The common populace of a state, the people.
- (greek history) municipality, an administrative area covering a city or several villages together
- first-person plural preterite indicative of dar
- Plural form of demo
demos (infinitive dar)