Definition of "profound"

A gulf profound as that Serbonian bog

1667, John Milton, “(please specify the book number)”, in Paradise Lost. […], London: […] [Samuel Simmons], […]; republished as Paradise Lost in Ten Books: […], London: Basil Montagu Pickering […], 1873,

Where no motives of interest or pride intervene, none can equal them for profound and philosophical views of society, ….

1819, Washington Irving, The Sketch Book, English Writers on America

How now! which of your hips has the most profound sciatica?

c. 1603–1604 (date written), William Shakespeare, “Measure for Measure”, in Mr. William Shakespeares Comedies, Histories, & Tragedies […] (First Folio), London: […] Isaac Iaggard, and Ed[ward] Blount, published 1623, (please specify the act number in uppercase Roman numerals, and the scene number in lowercase Roman numerals)

Of the profound corruption of this class there can be no doubt.

1860, Henry Hart Milman, History of Latin Christianity : including that of the popes to the pontificate of Nicholas V.

It’s probably one of the reasons the Shamima Begum case is having such a profound impact; one-dimensional stereotypes about Muslim women already run so deep.

2019, Shelina Janmohamed, “Long before Shamima Begum, Muslim women were targets”, in Guardian‎

I visited the wreckage at Ladbroke Grove, Hatfield. Potters Bar and Heck, and the experiences had a profound effect on me - especially Ladbroke Grove.

2023 September 20, Nigel Harris, “Comment Special: And it's goodbye from me...”, in RAIL, number 992, page 3

And with this, and a profound bow to his patrons, the Manager retires, and the curtain rises.

1847 January – 1848 July, William Makepeace Thackeray, Vanity Fair […], London: Bradbury and Evans […], published 1848

What humble gestures! What profound reverence!

a. 1662, Brian Duppa, Holy Rules and Helps to Devotion, published 1683

God, in the fathomlesse profound / Hath all his choice Commanders drown'd.

1638, George Sandys, A Paraphrase vpon the Divine Poems, Exodvs 15

[…] if some other place, / From your dominion won, th' Ethereal King / Possesses lately, thither to arrive / travel this profound. Direct my course […]

1667, John Milton, “Book II”, in Paradise Lost. […], London: […] [Samuel Simmons], […]; republished as Paradise Lost in Ten Books: […], London: Basil Montagu Pickering […], 1873, lines 976-980

But no man is likely to profound tbe Ocean of that Doctrine

1650, Thomas Browne, Pseudodoxia Epidemica: […], 2nd edition, London: […] A[braham] Miller, for Edw[ard] Dod and Nath[aniel] Ekins, […]