adj. 25B6; adjective
pestilential fever : PLAGUE-LIKE, infectious, contagious, communicable, epidemic, virulent; informal catching; poetic/literary pestiferous.
(informal) a pestilential man! : ANNOYING, irritating, infuriating, exasperating, maddening, tiresome, irksome, vexing, vexatious; informal aggravating, pesky, infernal.