jugate
n.— «According to Warlick, the popularity of a president, the quantity of buttons produced and the design content are key factors. Buttons with photographs are always more sought after by collectors. Buttons that include both the presidential and vice-presidential candidates are called jugates and are highly prized, especially if they include photographs of the candidates.» —“WorthPoint Political Memorabilia Expert Releases USA Button Poll Revealing Likely Presidential Winner” MarketWatch Oct. 31, 2008. (source: Double-Tongued Dictionary)