When the optometrist says that you have “20/20 vision” he is referring to your visual acuity, which is the clarity or sharpness of your vision.
What is 20/20 Vision?
Deconstructing the 20-20-20 Rule for digital eye strain
20/20 Vision is Not Perfect Vision (20/20 Vision Explained)
Vision Requirements & Care for Professionals
What glasses should I get for 20/30 vision? - Quora
What is 20/20 Vision? How to Convert Diopters to a 20/20 Measure
20/20 Vision: What Does it Mean?
What does 20/20 vision mean? - Interactive Mathematics
I Have 20/100 Vision: What Does That Mean?
Visual Acuity: The True Meaning of 20/20 Vision
What does 20/20 vision mean? - Interactive Mathematics
What does 20/20 vision actually mean?
Visual Acuity: The True Meaning of 20/20 Vision
Vision Is Our Dominant Sense