A Special Needs Trust is a unique type of trust specifically authorized by Congress, that when properly drafted, may enable a person under a physical or mental disability, or an individual with a chronic or acquired illness, to hold, in Trust, an unlimited amount of assets, without those assets being considered countable assets for purposes of qualification for governmental benefits that are based upon need.
"Special needs" is just a term to describe any trust intended to provide benefits without causing the beneficiary to lose public benefits he or she is entitled to receive.