英语词源字典 - 在线词源网站

flagship (n.)[flagship 词源字典]: also flag-ship, 1670s, a warship bearing the flag of an admiral, vice-admiral, or rear-admiral, from flag (n.) + ship (n.). Properly, at sea, a flag is the banner by which an admiral is distinguished from the other ships in his squadron, other banners being ensigns, pendants, standards, etc. Figurative use by 1933.[flagship etymology, flagship origin, 英语词源]
flagstaff (n.): 1610s, from flag (n.) + staff (n.). The settlement in Arizona, U.S., said to have been so called for a July 4, 1876, celebration in which a large flag was flown from a tall tree.
flagstone (n.): "any rock which splits easily into flags," 1730, from flag (n.2) "flat, split stone" + stone (n.).