wasabi Syllabification: (wa·sa·bi)Pronunciation: /wəˈsäbē/Definition of wasabi noun a Japanese plant with a thick green root that tastes like strong horseradish and is used in cooking, especially in powder or paste form as an accompaniment to raw fish. Eutrema wasabi, family Brassicaceae Origin: early 20th century: from Japanesewasabi in other Oxford dictionaries Definition of wasabi in the British & World English dictionary