An Etymological Dictionary of the German Language/Annotated/berüchtigt
berüchtigt, ‘infamous, notorious,’ a participle adjective from a weak verb used even by Luther — berüchtigen, ‘to defame,’ for. which berüchten was the common form in the 16th and 17th centuries. Compare Gerücht, as well as anrüchig and ruchbar; all these words are cognate with rufen, and are derived, as is shown by the ch for f before t, from Low German.