The Collaborative International Dictionary of English v.0.48:
Bubonic \Bu*bon"ic\ (b[-u]*b[o^]n"[i^]k), a. Of or pertaining to a bubo or buboes; characterized by buboes. [1913 Webster]WordNet (r) 3.0 (2006):
bubonic adj 1: of or evidencing buboes; "bubonic plague"