Definition of "gonzo"

I ask Hunter to explain... Just what is Gonzo Journalism?.. “Gonzo all started with Bill Cardosa [sic],..after I wrote the Kentucky Derby piece for Scanlan's..the first time I realized you could write different. And..I got this note from Cardosa saying, ‘That was pure Gonzo journalism!’.. Some Boston word for weird, bizarre.”

1972, Richard Pollack, chapter VI, in Stop the Presses, I Want to Get Off!

Nicholson’s Torrance is an evil clown […] Appropriately, pop culture has embraced him as a gonzo antihero: ads for T-shirts emblazoned with the “Here’s Johnny” Nicholson

2007, Mark Dery, The Pyrotechnic Insanitarium: American Culture on the Brink‎, page 121

Johnson abandoned all of these [values] for a narcissism that mocked the style of straightforward, sober, serious, self effacing politics of the post-war era. He turned his back on the public domain and the ideas of duty, honour and obligation that defined it. For him, politics was a personal story which saw the evolution of Britain's first gonzo political journalist into our first gonzo prime minister.

2021, Peter Oborne, The Assault on Truth, Simon and Schuster, page 62

“Unstable,” indeed! Those swine. Next year we should demand a Gonzo category—or maybe RS should give it. Of course. “The First Annual Rolling Stone Award for the Year's Finest Example of Pure Gonzo Journalism.”

2000, Hunter S. Thompson, Douglas Brinkley, Fear and Loathing in America: The Brutal Odyssey of an Outlaw Journalist, 1968-1976