Highway Code vs codification

Highway Code and codification both are nouns.

Word	Noun	Adjective	Verb	Adverb
Highway Code	Yes	No	No	No
codification	Yes	No	No	No

As nouns, codification is a hypernym of Highway Code; that is, codification is a word with a broader meaning than Highway Code:

Highway Code: the code of rules governing the use of public roads
codification: a set of rules or principles or laws (especially written ones)

Other hypernyms of Highway Code include code.

Highway Code (noun)	codification (noun)
the code of rules governing the use of public roads	the act of codifying; arranging in a systematic order
	a set of rules or principles or laws (especially written ones)