China; the People's Republic of China; also referred to as the Middle Kingdom

seas and oceans; the vast body of saltwater covering most of the Earth's surface

an office; a bureau; a government department or an agency for public services; also used as a name for certain shops like a bookstore or pharmacy

maritime surveillance and patrol; government agency or officer responsible for monitoring and protecting maritime interests (short for 中国海洋局海监 zhōng​guó​hǎi​yáng​jú​hǎi​jiān)