SSI Supplemental Security Income.-related category A letter code that identifies the program and type of medical benefits received.

A Medical Assistance category that has the same requirements as the corresponding category of SSI. Persons who receive Medical Assistance in SSI-related categories are aged, blind, or disabled Describes a person who (a) has a physical or mental impairment that substantially limits one or more life activities (for example, caring for one’s self, performing manual tasks, walking, seeing, hearing, speaking, learning, or working); (b) has a record of an impairment (has a history of, or has been misclassified as, having a mental or physical impairment) that substantially limits one or more major life activities; or (c) is regarded as having an impairment..