different between bifocals vs trifocals
bifocals
English
Etymology
From bi- + focal (see focus), coined in 1824 by John Isaac Hawkins, inventor of trifocals. When the concept of bifocals was originally conceived by Benjamin Franklin, he called them double spectacles.
Noun
bifocals pl (plural only)
- Spectacles that have corrective lenses of two different powers; used by people who need both distance and reading glasses.
Related terms
- bifocal
- trifocals
Translations
bifocals From the web:
- what bifocals do i need
- what bifocals are used for
- bifocals meaning
- bifocals what are they
- bifocals what does it do
- what do bifocals look like
- what does bifocals mean
- what are bifocals glasses
trifocals
English
Etymology
From tri- + focal (see focus). Coined by John Isaac Hawkins, their inventor, in 1826.
Noun
trifocals pl (plural only)
- (optics) Spectacles with corrective lenses that have three different powers per eye.
Related terms
- bifocals
- trifocal
Translations
trifocals From the web:
- what are trifocals used for
- what do bifocals look like
- what do bifocals do
- what does trifocals
- what are trifocals bifocals
- what are trifocals for
Share
Tweet
+1
Share
Pin
Like
Send
Share
you may also like
- bifocals vs trifocals
- award vs reward
- distinct vs distinctive
- arteriosclerosis vs atherosclerosis
- annual vs perennial
- amend vs emend
- allude vs elude
- aldehyde vs formaldehyde
- affection vs affectation
- adherent vs adherence
- secretion vs secret
- acclimatize vs acclimation
- accelerate vs accelerograph
- academic vs academical
- academician vs academia
- nvram vs ram
- dram vs ram
- sram vs ram
- teuton vs dutch
- dutchland vs dutch