Philippic.
Noun.
A discourse or declamation full of bitter condemnation: Tirade.
Origin: Middle French philippique, from Latin and Greek; Latin philippica, orationes philippicae, speeches of Cicero against Mark Antony, translation of Greek Philippikoi logoi, speeches of Demosthenes against Philip II of Macedon. Literally, speeches relating to Philip. (1592).
“That was the kind of outburst Stefan had to put up with for five years as I worked on the Wharton bibliography, wading through file cards and fits. The explosion would usually be followed by an overly detailed explanation of what I was reading, then a philippic of one form or another. No wonder he was sick of everything Wharton.” – The Edith Wharton Murders, Lev Raphael.