Source : WordNet®

mononucleosis
     n : an acute disease characterized by fever and swollen lymph
         nodes and an abnormal increase of mononuclear leucocytes
         or monocytes in the bloodstream; not highly contagious;
         some believe it can be transmitted by kissing [syn: {infectious
         mononucleosis}, {mono}, {glandular fever}, {kissing
         disease}]