There are a number of synonyms for the word "cyclopel," which is a term that describes a lens that has a single curved surface and is used in a variety of optical instruments. Some of the most common synonyms for this term include unifocal, monofocal, and single-focus lenses. Other synonyms for cyclopel may include convex lenses, concave lenses, and plano-convex lenses, depending on the specific shape and properties of the lens in question. Regardless of the specific terminology used, the common thread among all of these synonyms is that they describe lenses that have a singular focus and are used to help improve vision or focus light in a particular way.