Persian walnut per·sian·wal·nut uncommon noun 1. Eurasian walnut valued for its large edible nut and its hard richly figured wood; widely cultivated SynonymsEnglish walnutEnglish walnut treeCircassian walnutPersian walnutJuglans regia Related words Broader terms walnut Parts Juglans Part of English walnut WordNet 2.1 (Princeton University). WordNet 2.1 Copyright Princeton University. All rights reserved.