unwritten law vs practice

unwritten law and practice both are nouns.

Word	Noun	Adjective	Verb	Adverb
unwritten law	Yes	No	No	No
practice	Yes	No	Yes	No

As nouns, practice is a hypernym of unwritten law; that is, practice is a word with a broader meaning than unwritten law:

Other hypernyms of unwritten law include pattern.

unwritten law (noun)	practice (noun)
law based on customary behavior	a customary way of operation or behavior
	systematic training by multiple repetitions
	the exercise of a profession
	translating an idea into action
	knowledge of how something is usually done

unwritten law (verb)	practice (verb)
	learn by repetition
	engage in a rehearsal (of)
	carry out or practice; as of jobs and professions
	avail oneself to
	engage in or perform