Paraplegia is an impairment in motor or sensory function of the lower extremities.
The word comes from Ionic Greek (παραπληγίη) "half-stricken".
The area of the spinal canal that is affected in paraplegia is either the thoracic, lumbar, or sacral regions.
If four limbs are affected by paralysis, tetraplegia or quadriplegia is the correct term.
If only one limb is affected, the correct term is monoplegia.