Wiktionary
tertium quids
n. (tertium quid English)
Wikipedia
Tertium quids
The tertium quids (sometimes shortened to quids) refers to various factions of the American Democratic-Republican Party during the period 1804–1812. In Latin, tertium quid means "a third something". Quid was a disparaging term that referred to cross-party coalitions of Federalists and moderate Democratic-Republicans.