a funeral oration; an impassioned oration; to make / deliver / pronounce an oration
1752, Samuel Johnson, The Rambler, No. 207, 10 March, 1752, in Volume 6, London: J. Payne and J. Bouquet, 1752, p. 279,
The masters of rhetorick direct, that the most forcible arguments be produced in the latter part of an oration, lest they should be effaced or perplexed by supervenient images.
(humorous) A lengthy speech or argument in a private setting.
(Catholicism) A specific form of short, solemn prayer said by the president of the liturgical celebration on behalf of the people.
verb
To deliver an oration; to speak.
1633, John Donne (attributed translator), The Auncient History of the Septuagint. Written in Greeke, by Aristeus 1900. yeares since, London, p. 80, cited in Henry Todd, A Dictionary of the English Language, London: Longman, Hurst, Rees, Orme, and Brown, 1818, Volume 3,
They gave answers with great sufficiency touching all difficulties concerning their own law, and had marvellous promptitude both for orationing and giving judgement.
1764, Samuel Foote, The Mayor of Garratt, Act II, in The Dramatic Works of Samuel Foote, Dublin: S. Price et al., 1778, Volume 1, p. 286,
[…] Master Primmer is the man for my money; a man of learning; that can lay down the law: why, adzooks, he is wise enough to puzzle the parson: and then, how you have heard him oration at the Adam and Eve of a Saturday night, about Russia and Prussia […]