The term "re-lucent" refers to something that becomes shiny or bright again after polishing or cleaning. As an antonym, there are several words that can be used to describe something that lacks luster or shine. These words include dull, faded, cloudy, matte, tarnished, and dingy. These terms indicate a lack of brightness or reflectivity as opposed to "re-lucent," which implies a renewed sheen. When choosing an opposite word for "re-lucent," these terms can be used to describe objects that are dull or lackluster, such as tarnished silverware or faded photographs.