The word "vitreousness" refers to the quality or state of being glassy or translucent. Some synonyms that can be used instead of this term are lucidity, clarity, transparency, and brilliance. These words can be used to describe the appearance of glass, crystal, or other transparent materials. Other related synonyms could include sheen, luster, shine, and gleam. In a figurative sense, "vitreousness" can also be used to describe a state of clarity or transparency in language, thought or behavior. In this context, synonyms could include openness, honesty, sincerity, and directness.