Bubonic: relative or belonging to Bubo or buba, as said Alfredo Edgardo, small tumor or lump of a lymph node in any area of the body, preferably in the armpits, groin or neck as a result of diseases such as bubonic plague, tuberculosis, gonorrhea, chancroid and syphilis. The bubonic plague, or black death of the 14th century was the most devastating of all human history affecting Europe, China, India, Middle East and North Africa, dying, according to some estimates, more than 100 million people. Florence ( 41 Italy; in the mid-14th century survived only a fifth of the population. The cause of the disease is in the bacterium yersinia pestis, transmitted to humans through rats and fleas.