any of several perennial herbs of the genus Petasites in the composite family,native to northern temperate regions and having large basal leaves and dense clusters of usually whitish or purplish flower heads是什么意思_any of several perennial herbs of the genus Petasites in the composite family,native to northern temperate regions and having large basal leaves and dense clusters of usually whitish or purplish flower heads在线翻译_英语_读音_用法_例句