The Collaborative International Dictionary of English v.0.48:

Cephalalgia \Ceph`a*lal"gi*a\, Cephalalgy \Ceph"a*lal`gy\, n.
   [L. cephalalgia, Gr. ?; ? + ? pain: cf. F. c['e]phalalgie.]
   (Med.)
   Pain in the head; headache.
   [1913 Webster]