Definition of "flagitious"

This young Nobleman was not only a flagitious Punster himself, but was accessary to the Punning of others, by Consent, by Provocation, by Connivance, and by Defence of the Evil committed […] .

1716 Nov 7th, quoted from 1742, probably Alexander Pope, God's Revenge Against Punning, from Miscellanies, 3rd volume, page 227

The duke found his soldiery half disciplined, flagitious, disorderly and inefficient: he rendered them, in his own words, a "perfect organ."

1842, [anonymous collaborator of Letitia Elizabeth Landon], chapter XLIV, in Lady Anne Granard; or, Keeping up Appearances. […], volume II, London: Henry Colburn, […], page 258

As flagitious as he can be, Mr. Trump has been a legitimate news figure and, thus, what he had to say should be aired.

2020 December 31, Kara Swisher, “Goodbye, Twitter Trump! And Other Predictions for 2021”, in The New York Times‎

But if in Noble Minds ſome Dregs remain, / Not yet purg'd off, of Spleen and ſow'r Diſdain, / Diſcharge that Rage on more Provoking Crimes, / Nor fear a Dearth on theſe Flagitious Times.

1709, [Alexander Pope], An Essay on Criticism, London: […] W. Lewis […], published 1711, page 30

As he entered he boomed: "Monstrous! Flagitious!"

1959, Rex Stout, “Assault on a Brownstone”, in Death Times Three, published 1985, page 186