Definition of "bombast"

SURBATING; a Diſtemper in a Horſe, who is ſaid to be ſurbated, when the Sole is worn, bruiſed or ſpoiled by travelling without Shoes, or with ill ſhoeing: [...] take Frankincenſe, and rolling it in a little fine Cotton Wool or Bombaſt, with a hot Iron melt it into the Foot betwixt the Shoe and the Toe, until the Orifice, where the Blood was taken away, is fill'd up; [...]

1725, [Noël] Chomel, “SURBATING”, in R[ichard] Bradley, editor, Dictionaire Oeconomique: Or, The Family Dictionary. […], volumes II (I–Z), London: […] D[aniel] Midwinter, […], column 2

This strange wool-bearing plant is of the mallow tribe. [...] Another name formerly given to the vegetable fleece was bombast. This word was in use before our ancestors were skilful enough to weave the cotton wool which was brought to them from the East in the merchant ships of Venice and Genoa. What they did not want for candle-wicks, they employed in stuffing and wadding their doublets and other articles of dress.]

, S. W[arren], “The Wool-bearing Shrub”, in Cotton, London: Society for Promoting Christian Knowledge; New York, N.Y.: Pott, Young, & Co., page 14

[C]ertayne I am there was neuer any kinde of apparell euer inuented, that could more diſproportion the body of man, then theſe Dublettes with great bellies hanging downe beneath their Pudenda, (as I haue ſayd) & ſtuffed with foure, fiue, or ſixe pound of Bombaſt at the least: [...]

1585, Phillip Stubbes [i.e., Philip Stubbs], The Anatomie of Abuses: Contayning a Discouerie, or Briefe Summarie of such Notable Vices and Imperfections, as now Raigne in Many Christian Countreyes of the Worlde: […], 3rd edition, London: […] Richard Iones, […], folio 23, recto and verso

Heere comes leane Iacke, heere comes bare-bone. How now my ſweet Creature of Bombaſt, how long is't agoe, Iacke, ſince thou ſaw'ſt thine owne Knee?

c. 1597 (date written), William Shakespeare, “The First Part of Henry the Fourth, […]”, in Mr. William Shakespeares Comedies, Histories, & Tragedies […] (First Folio), London: […] Isaac Iaggard, and Ed[ward] Blount, published 1623, [Act II, scene iv], page 58, column 1

Bombaſt and Buffoonry, by Nature lofty and light, ſoar higheſt of all, [...]

1704, [Jonathan Swift], “Section I. The Introduction.”, in A Tale of a Tub. […], London: […] John Nutt, […], page 40

And let burleſque in ballads be employ'd; / Yet noiſy bombaſt carefully avoid, / Nor think to raiſe, tho on Pharſalia's plain, "Millions of mourning mountains of the ſlain:" [...]

1760, John Dryden, “The Art of Poetry”, in Samuel Derrick, editor, The Miscellaneous Works of John Dryden, Esq; Containing All His Original Poems, Tales, and Translations. […], volume I, London: […] J[acob] and R[ichard] Tonson […], canto I, pages 320–321

Upon a little serious examination, the off-hand disposal of an important question of policy, by the declaration that Americans can do anything, proves to be only a silly piece of bombast, and, upon a little reflection, we find that our hands are quite full at home of problems, by the solution of which the peace and happiness of the American people could be greatly increased.

1899 January 16, William G[raham] Sumner, The Conquest of the United States by Spain: A Lecture before the Phi Beta Kappa Society of Yale University, January 16, 1899, Boston, Mass.: Dana Estes & Company, […], page 30

At least for one night, Donald Trump put aside the bombast and bellicosity of a campaign that seemed to bleed into his presidency.

2017 March 1, Anthony Zurcher, “Trump addresses Congress: A kinder, gentler president”, in BBC News‎, archived from the original on 5 June 2017

Their doctrine is to be seen in Jacob Behmen's books by him that hath nothing else to do, than to bestow a great deal of time to understand him that was not willing to be easily understood, and to know that his bombasted words do signify nothing more than before was easily known by common familiar terms.

1820, Samuel Taylor Coleridge, “Notes on [Richard] Baxter’s Life of Himself”, in Henry Nelson Coleridge, editor, The Literary Remains of Samuel Taylor Coleridge, volume IV, London: William Pickering, published 1839, page 90

[']The ugly truth is, Gerald,' she said viciously, 'that you're a phoney, a rotten, bombasting phoney, trying to cover up from all the world, […][']

1968, Christianna Brand, What Dread Hand?: A Collection of Short Stories, London: Michael Joseph

But he (as louing his owne pride, and purpoſes) / Euades them, with a bumbaſt Circumſtance, / Horribly ſtufft with Epithites of warre, / Non-ſuites my Mediators.

c. 1603–1604 (date written), William Shakespeare, “The Tragedie of Othello, the Moore of Venice”, in Mr. William Shakespeares Comedies, Histories, & Tragedies […] (First Folio), London: […] Isaac Iaggard, and Ed[ward] Blount, published 1623, [Act I, scene i], page 310, column 1

'Tis not ſuch Lines as almoſt crack the Stage. / When Bajazet begins to rage. / Nor a tall Met'phor in the Bombaſt way, / Nor the dry chips of ſhort-lung'd Seneca.

1678, Abraham Cowley, “Ode. Of Wit.”, in The Works of Mr. Abraham Cowley. , stanza 7, page 3