argon

n [U] chemical element, an almost inert gas present in the atmosphere 氩. =>App 10 见附录10.

archive, archives, archivist, archway, Arctic, Arctic Circle, ardent, ardently, ardor, ardour (US ardor), arduous, arduously, are, area, area code (US) dialling code, areca, areca nut (also betel-nut), aren't, arena, arete, argot, arguable, arguably, argue, argument, argumentation, argumentative, argumentatively, argy-bargy, aria, arid, aridity, aridly, aridness, Aries, aright, arise, arisen, aristocracy, aristocrat,