The aboriginal people ‘discovered’ – and enjoyed, the nuts. Ferdinand Muller described the genus scientifically and named it in honour of his colleague: ".... a beautiful genus dedicated to Dr John Macadam, M.D. the talented and deserving secretary of our institute" (the Philosophical Institute of Victoria, now the Royal Society of Victoria).
Ferdinand von Mueller was a German - Australian botanist.
For further information see:
The author of the latter, John Macadam, is a descendant of Dr Macadam's younger brother.