Formal, somewhat stiff term for a mistake or error, often used in writing or serious discussion.
A serious error was found in the report.
Technical use in logic and philosophy for a fallacy in reasoning.
That argument contains a logical fallacy.
誤謬 is a highbrow, academic term for a logical or reasoning error, while 誤り is the everyday formal word covering any kind of mistake.
Sino-Japanese compound of 誤 (go, 'mistake') and 謬 (byū, 'error, fallacy'). The reading ごびゅう is the standard on'yomi.