jugate
A portrait which depicts two side-by-side subjects with relative proximity.
More than 50 celluloid and lithographed tin political jugates [i.e., pinback buttons with jugate portraits] made since 1896 sold at three different summer auctions […] You can find jugate trays, posters, badges and ribbons, too.
Where it comes from
Borrowed from Latin iugātus (“yoked together in pairs”), perfect passive participle of iugō (“to yoke”), see -ate (adjective-forming suffix) and -ate (noun-forming suffix).
Adapted from the Wiktionary entry jugate (CC BY-SA 4.0).