* Bifocals describe a type of eyeglasses. An antonym would need to describe a different type of eyewear.
* "Not bifocals" could be considered an antonym, but it's not a single word.
Instead of an antonym, you could consider synonyms or descriptive phrases:
* Single vision glasses: These have one lens strength for either near or far vision.
* Progressive lenses: These offer a smoother transition between near and far vision than bifocals.
* Monovision: This is a technique where one eye is corrected for near vision and the other for far vision.
* Contact lenses: Can be used for nearsightedness, farsightedness, or presbyopia (the need for reading glasses).
The best alternative depends on the context of your sentence. Consider what you want to emphasize and choose the appropriate word or phrase.