| Word | Definitions | Synonyms |
|---|---|---|
| dioptre | (noun) a unit of measurement of the refractive power of a lens which is equal to the reciprocal of the focal length measured in meters; used by oculists | Synonyms: diopter |
| sceptre | (noun) a ceremonial or emblematic staff | Synonyms: scepter, verge, wand |
| (noun) the imperial authority symbolized by a scepter | Synonyms: scepter |