The chemical element radon.
1Niger (international vehicle registration).
2(chiefly in North America) Registered Nurse.
3(in the UK) Royal Navy.
1(chiefly in North America) Registered Nurse.
2
英汉双解词典包含464360条英汉词条，基本涵盖了全部常用单词的翻译及用法，是英语学习的有利工具。