Rimless
Glasses with no rim around the lenses; the bridge and arms are fixed straight to the lenses.
Also: rimless glasses, frameless
Rimless glasses have drilled lenses with the bridge and temple arms attached by small screws or plugs. With no frame front they are very light and say little about a face shape, which is why opticians suggest them for people who want glasses to recede. They were popular from the 1880s to the 1930s and again from the 1990s. The lenses must be tough, so polycarbonate and similar materials are used.