Definition of "philippic"

[…] the Bema, from whence Demosthenes thundered his philippics and fired the wavering patriotism of his countrymen.

1869, Mark Twain [pseudonym; Samuel Langhorne Clemens], chapter XXXII, in The Innocents Abroad, or The New Pilgrims’ Progress; […], Hartford, Conn.: American Publishing Company. […], page 348

Mrs. Ferrars looked exceedingly angry, and drawing herself up more stiffly than ever, pronounced in retort this bitter phillipic; “Miss Morton is Lord Morton’s daughter.”

1811, [Jane Austen], chapter XII, in Sense and Sensibility […], volume II, London: […] C[harles] Roworth, […], and published by T[homas] Egerton, […], page 234

"Sir Robert Akhurst is a good man, a very good man, notwithstanding his philippic; but he is an old one, which makes all the difference."

1842, [anonymous collaborator of Letitia Elizabeth Landon], chapter XXXVII, in Lady Anne Granard; or, Keeping up Appearances. […], volume II, London: Henry Colburn, […], page 172

Skin-the-Goat, assuming he was he, evidently with an axe to grind, was airing his grievances in a forcible-feeble philippic anent the natural resources of Ireland, or something of that sort, which he described in his lengthy dissertation as the richest country bar none on the face of God’s earth, far and away superior to England

1922 February, James Joyce, Ulysses, Paris: Shakespeare and Company, […]

As a young man, Lytton Strachey admired Hastings and wrote a long thesis on him, while dismissing Burke as ‘an ignorant enthusiast’. What strikes me on rereading those great philippics is, on the contrary, their exactness and perceptiveness.

2017 September 7, Ferdinand Mount, “Umbrageousness”, in London Review of Books‎