The angle subtended by an object at a given distance.

The apparent size of an object as seen by an observer; expressed in units of degrees (of arc), arc minutes, or arc seconds. The moon, as viewed from the Earth, has an angular diameter of one-half a degree.

The apparent size of an object expressed as an angle. It is measured in degrees, minutes and seconds.

the apparent width of an object as seen by an observer, usually expressed in degrees, arcminutes, or arcseconds

the apparent size of an object measured by the angle between two lines of sight along each side of an object. An object's actual linear diameter can be found from the angular size if the distance is already known. The linear diameter = (2/360°) × (its distance × angular size in degrees).

The apparent size of an object, measured by the angle the object subtends, in degrees of arc, minutes or arc, or seconds of arc.

Angular size is a measurement of how large or small something is using rotational measurement. It is useful for measuring things that are so far away that they appear two-dimensional.