Definition of "bonkers"

[A]nd we should remind ourselves that it is absolutely bonkers that we elect judges at all; that system is used almost nowhere else on earth[.]

2021, Paul Waldman, Opinion: The Supreme Court won’t stand up for voting rights. But some state courts will, in: The Washington Post, July 6 2021 (emphasis in original)

"They are turning people off travelling. And the removal of catering on such a long-distance route is just bonkers."

2021 December 29, Paul Clifton, “"Crisis" on the West of England line”, in RAIL, number 947, page 35