Angular distance and Hour angle

Angular distance noun - The angular separation between two objects as perceived by an observer.

Hour angle and angular distance are semantically related. In some cases you can replace phrase "Hour angle" with "Angular distance", this phrases are similar.

Hour angle noun - (astronomy) the angular distance of a celestial point measured westward along the celestial equator from the zenith crossing; the right ascension for an observer at a particular location and time of day.

Angular distance and hour angle are semantically related. You can use "Angular distance" instead a noun phrase "Hour angle".