An Etymological Dictionary of the German Language/Annotated/Lambertsnuß

Lambertsnuß, feminine, ‘filbert,’ instinctively connected by Germans with St. Lambert, but the historic term is lombardische Nuß, ‘Lombard nut’; Middle High German Lambardîe, Lombardîe, and Lámpart,’ ‘Lombardy, Italy.’ Compare Walnuß.