part to whole relation vs meronymy

part to whole relation and meronymy both are nouns.

Word	Noun	Adjective	Verb	Adverb
part to whole relation	Yes	No	No	No
meronymy	Yes	No	No	No

As nouns, part to whole relation and meronymy are synonyms defined as:

part to whole relation and meronymy: the semantic relation that holds between a part and the whole

part to whole relation (noun)	meronymy (noun)
the semantic relation that holds between a part and the whole	the semantic relation that holds between a part and the whole