The horizontal angle of the observer`s bearing in surveying, measured clockwise from a referent direction, as from the north, or from a referent celestial body, usually Polaris.是什么意思_The horizontal angle of the observer`s bearing in surveying, measured clockwise from a referent direction, as from the north, or from a referent celestial body, usually Polaris.在线翻译_英语_读音_用法_例句