Magnifier/ˈmæɡnɪfaɪər/ Definition 1 of 2Pro Tip 1/3Visual Aid Magnifiers help people with poor eyesight read small text. Grandma used her magnifier to enjoy her favorite novel. Pro Tip 2/3Not Always Glass Magnifiers come in different forms, like plastic lenses or electronic screens. The scientist used a plastic magnifier to inspect the plant. Pro Tip 3/3Physical Object Most often, a magnifier is a handheld object you can move around. The jeweler grabbed a magnifier to examine the diamond closely.