writing vs patristics

writing and patristics both are nouns.

Word	Noun	Adjective	Verb	Adverb
writing	Yes	No	No	No
patristics	Yes	No	No	No

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

Other hyponyms of writing include patrology.

writing (noun)	patristics (noun)
the activity of putting something in written form	the study of the lives, writings, and doctrines of the Church Fathers
the act of creating written works	the writings of the early Church Fathers
the work of a writer; anything expressed in letters of the alphabet (especially when considered from the point of view of style and effect)
letters or symbols that are written or imprinted on a surface to represent the sounds or words of a language
(usually plural) the collected work of an author