The populace is the ordinary people of a place. The general populace, the local populace, address the populace.
It is formal and faintly distancing, since it is a word used about people rather than by them. It is a different word from populous, meaning heavily peopled, and the two are confused in writing constantly.
1nounpopulaceThe ordinary people of a place.
“The king's new taxes angered the populace, and riots broke out in the capital.”
populace is a people.
Italian popolaccio, the common crowd, from popolo, people, from Latin populus.
Latin
populus
Italian
popolaccio
Middle French
populace
English, today
populace
Middle French populace, from Italian popolaccio, from popolo + -accio, from Latin populus.
Etymology from Wiktionary, CC BY-SA