Does being blind in one eye qualify as a disabilty?

Possibly. Your state has its own set of rules.Legal blindness is one criteria for disability, but this means poor vision in both eyes.
AMA 28% Impairment. The ama guides to the evaluation of permanent impairment define a rating schema that includes rules for describing a single percentage impairment rating. For acquired total blindness in one eye, the rating is 28% plus any adjustments for loss of binocularity and facial disfigurement. Legal blindness is established at a 50% impairment level. "a singular view" by frank b. Brady may help you.
A qualified yes. A partial disability does exist if one eye doesn't work. A complex calculation is required to determine how much of a disability. Most of the time, this is only done if the loss is work related. Such a disability does not qualify you as "legally blind"' however. This is defined as an inability to correct the better eye to 20/200!