Meanings of speculum include: Speculum (medical), a medical tool used for examining body cavities. Speculum metal, an alloy containing copper and tin used for making all-metal mirrors. A speculum metal mirror used in telescopes or early octants. A mirror, for example, a hand-held bronze mirror used by Etruscan women. Speculum feathers, the secondary feathers on the inner part of a duck's wing which are often brightly coloured. Speculum (journal), a journal of medieval studies published by… (More on Speculum)