GLOSSARY A–M

Speak fluent eyewear.

**Acetate** — Plant-based plastic (cotton fibers, wood pulp) cut into sheets, then shaped, tumbled, and polished into frames. **Anti-reflective** — A lens coating that cuts glare and ghost images. Also called AR. **Aspheric** — A flatter, thinner lens design that reduces the bulge in strong prescriptions. **Base curve** — The curvature of the lens front, matched to the frame's wrap. **Bifocal** — A lens with two powers: distance up top, reading in a visible lower segment. **Bridge** — The part that sits on your nose, connecting the two lens rims. **Cat-eye** — A frame with upswept outer corners. The 2026 version: subtle, lifting, almost predatory. **Coating** — A thin lens treatment: anti-scratch, anti-reflective, UV, or hydrophobic. **Cylinder** — The lens power that corrects astigmatism. On your prescription as "CYL." **Diopter** — The unit of lens power. Higher number, stronger correction. **High-index** — Denser lens plastic that makes strong prescriptions thinner and lighter. Common: 1.67, 1.74. **Hinge** — The joint where temple meets front. The smallest part doing the most work. **Lenticular** — A lens ground thin at the edges with a central optical zone, for very strong prescriptions. **Monocle** — One lens, one eye, zero temples. A vibe more than a vision plan. **Multifocal** — Any lens with more than one power: bifocals, trifocals, progressives.