From The Collaborative International Dictionary of English v.0.48 :
Paraplegia \Par`a*ple"gi*a\, Paraplegy \Par"a*ple`gy\, n. [NL.
paraplegia, fr. Gr. ? hemiplegia, fr. ? to strike at the
side; para` beside + ? to strike: cf. F. parapl['e]gie.]
(Med.)
Palsy of the lower half of the body on both sides, caused
usually by disease of the spinal cord. -- Par`a*pleg"ic, a.
[1913 Webster]
From WordNet (r) 3.0 (2006) :
paraplegia
n 1: paralysis of the lower half of the body (most often as a
result of trauma)