flagship
n
1 ship which has the commander of a fleet on board 旗艦.
2 (fig 比喻) most important of a group of products, projects, services, etc (一批產品、 工程、 服務設施等中)最重要者
This dictionary is the flagship of Oxford's range of learners' dictionaries. 本詞典執牛津一系列學習者詞典之牛耳.