The Collaborative International Dictionary of English v.0.48:

Anaemia \A*n[ae]"mi*a\, Anemia
\A*ne"mi*a\([.a]*n[=e]"m[i^]*[.a]), a. [NL., fr. Gr. 'anaimi`a;
   'an priv. + a'i^ma blood.] (Med.)
   A morbid condition in which number of the red blood cells or
   concentration of hemoglobin decreases below that of normal.
   [1913 Webster + AS]

WordNet (r) 3.0 (2006):

anemia
    n 1: a deficiency of red blood cells [syn: anemia, anaemia]
    2: a lack of vitality [syn: anemia, anaemia]
    3: genus of terrestrial or lithophytic ferns having pinnatifid
       fronds; chiefly of tropical America [syn: Anemia, genus
       Anemia]