lunar

腕部近侧腕骨系列中间的一块骨头,呈半月形。

The middle bone of the proximal series of the carpus in the wrist, which is shaped like a half-moon.

观测月球与其他天体的角距,尤其用于确定船舶在海上经度的方法。

An observation of a lunar distance (“the angle between the Moon and another celestial body”), especially for establishing the longitude of a ship at sea.