The definition of disability under Social Security is different than other programs. Social Security pays only for total disability. No benefits are payable for partial disability or for short-term disability.
Disability under Social Security is based on your inability to work. SSA considers you disabled under Social Security rules if you cannot do work that you did before and SSA decides that you cannot adjust to other work because of your medical condition(s). Your disability must also last or be expected to last for at least one year or to result in death.
This is a strict definition of disability. Social Security program rules assume that working families have access to other resources to provide support during periods of short-term disabilities, including workers' compensation, insurance, savings and investments.
Social Security Disability Insurance pays benefits to you and certain members of your family if you are "insured" meaning that you worked long enough and paid Social Security taxes.
Social Security Supplemental Income pay benefits based on financial need. When you apply for either program Social Security will collect medical and other information from you and make a decision about whether or not you meet Social Security's definition of disability.