trifocal
1
6.9
Glasses that have three lens parts for near, middle, and far vision
- adjective
- /ˈtraɪˌfoʊkəl/
- Specialized
:
trifocal
- trifocal lenses
Examples
-
Most seniors wear eyeglasses with bifocal or trifocal lenses.
Academic text (1997) -
Many seniors prefer trifocal lenses because they provide clearer vision for reading, computer use, and driving.
-
The optometrist recommended trifocal glasses to help me see better at different distances without switching lenses.
-
With trifocal lenses, I can easily transition from reading my book to looking at the television.
Synonyms
1
6.7
A lens with more than one focus to help see near and far
is specifically made with three focal points for near intermediate and distance
Surface Forms
trifocal positive
Morphology
Etymology
Trifocal is made of tri- meaning 'three', like in triangle, and focal from focus meaning 'a point for seeing'. So something described as trifocal has three focus areas to help you see near, middle, and far.