The word "biconvex" represents a lens or a surface that curves outward on both sides. It is commonly used in geometry and engineering to describe convex polygons or lenses. Some synonyms for biconvex include double-convex, biconvexoid, and symmetrically convex. Biconvex lenses are often used in optical instruments like projectors, cameras, and microscopes due to their ability to converge light rays. These lenses are also commonly used in eyeglasses and magnifying glasses to correct vision impairments and enhance visual clarity. The use of biconvex lenses has revolutionized many fields of science and technology, making them crucial components in many everyday devices we use today.