A visual acuity of 20/200 is considered low vision, not far removed from legal blindness. WebMD defines low vision as a visual acuity of between 20/70 and 20/200, with corrective measures such as eyeglasses employed.
WebMD characterizes legal blindness as "having visual acuity that, in both eyes, can't be corrected to better than 20/200," so 20/200 vision is bad enough that it is quite near the limit for legal blindness.
According to the American Optometric Association, or AOA, a person with 20/200 vision expects to see clearly at 20 feet what someone with normal vision sees at 200 feet. The AOA classifies 20/200 acuity as a severe visual impairment.