diurnal parallax vs parallax

diurnal parallax and parallax both are nouns.

Word	Noun	Adjective	Verb	Adverb
diurnal parallax	Yes	No	No	No
parallax	Yes	No	No	No

As nouns, parallax is a hypernym of diurnal parallax; that is, parallax is a word with a broader meaning than diurnal parallax:

diurnal parallax: the parallax of a celestial body using two points on the surface of the earth as the earth rotates
parallax: the apparent displacement of an object as seen from two different points that are not on a line with the object

diurnal parallax (noun)	parallax (noun)
the parallax of a celestial body using two points on the surface of the earth as the earth rotates	the apparent displacement of an object as seen from two different points that are not on a line with the object