orbit vs realm

orbit and realm both are nouns.

Word	Noun	Adjective	Verb	Adverb
orbit	Yes	No	Yes	No
realm	Yes	No	No	No

As nouns, realm is a hyponym of orbit; that is, realm is a word with a more specific, narrower meaning than orbit:

orbit (noun)	realm (noun)
an area in which something acts or operates or has power or control:	a knowledge domain that you are interested in or are communicating about
the bony cavity in the skull containing the eyeball	the domain ruled by a king or queen
the (usually elliptical) path described by one celestial body in its revolution about another	a domain in which something is dominant
the path of an electron around the nucleus of an atom
a particular environment or walk of life

orbit (verb)	realm (verb)
move in an orbit