| Word | Definitions | Synonyms |
|---|---|---|
| acuity | (noun) a quick and penetrating intelligence | Synonyms: acuteness, keenness, sharpness |
| (noun) sharpness of vision; the visual ability to resolve fine detail (usually measured by a Snellen chart) | Synonyms: sharp-sightedness, visual acuity | |
| vacuity | (noun) total lack of meaning or ideas | Synonyms: inanity, mindlessness, pointlessness, senselessness |
| (noun) a region that is devoid of matter | Synonyms: vacuum | |
| (noun) the absence of matter | Synonyms: vacuum |