Meaning
三つ葉 (みつば, Mitsuba) is Mitsuba — a Japanese food (leafy greens, plants).
What is Mitsuba?
Mitsuba (Japanese wild parsley, honeywort, Cryptotaenia japonica ) is commonly used as a garnish in soups or atop entrees or as a sushi ingredient. The sprouts are used in salads and soup. Like parsley, the flavor is clean and refreshing with a slightly bitter taste that some describe as celery-like. Mitsuba's dark green leaves, stems, and pods have an extensive nutritional profile, including high levels of calcium and vitamin C.