byname vs designation

byname and designation both are nouns.

Word	Noun	Adjective	Verb	Adverb
byname	Yes	No	No	No
designation	Yes	No	No	No

As nouns, designation is a hypernym of byname; that is, designation is a word with a broader meaning than byname:

byname: a familiar name for a person (often a shortened version of a person's given name)
designation: identifying word or words by which someone or something is called and classified or distinguished from others

Other hypernyms of byname include appellation, appellative, denomination.

byname (noun)	designation (noun)
a familiar name for a person (often a shortened version of a person's given name)	the act of putting a person into a non-elective position
	the act of designating or identifying something
	identifying word or words by which someone or something is called and classified or distinguished from others