[ 'spɛkjʊləm ]
■ noun ( plural specula -lə )
1》 Medicine a metal instrument that is used to dilate an orifice or canal in the body to allow inspection.
2》 Ornithology a bright patch of plumage on the wings of certain birds, especially ducks.
3》 a mirror or reflector, especially (formerly) a metallic mirror in a reflecting telescope.
↘short for ~ metal .
Origin
ME: from L., lit. 'mirror', from specere 'to look'.