interrelationship vs interrelatedness

interrelationship and interrelatedness both are nouns.

Word	Noun	Adjective	Verb	Adverb
interrelationship	Yes	No	No	No
interrelatedness	Yes	No	No	No

As nouns, interrelationship and interrelatedness are synonyms defined as:

interrelationship and interrelatedness: mutual or reciprocal relation or relatedness

Other synonyms of interrelationship include interrelation.

interrelationship (noun)	interrelatedness (noun)
mutual or reciprocal relation or relatedness	mutual or reciprocal relation or relatedness