What is permanent disability

[jerry2000]

Here is the IRS definition of Permanent and total disability:

Permanent and total disability. You are permanently
and totally disabled if you cannot engage
in any substantial gainful activity because
of your physical or mental condition. A qualified
physician must certify that the condition has lasted
or can be expected to last continuously for
12 months or more, or that the condition can be
expected to result in death.

IRS Publication 17, page 221
http://www.irs.gov/pub/irs-pdf/p17.pdf