smuggling vs importation

smuggling and importation both are nouns.

Word	Noun	Adjective	Verb	Adverb
smuggling	Yes	No	No	No
importation	Yes	No	No	No

As nouns, importation is a hypernym of smuggling; that is, importation is a word with a broader meaning than smuggling:

smuggling: secretly importing prohibited goods or goods on which duty is due
importation: the commercial activity of buying and bringing in goods from a foreign country

Other hypernyms of smuggling include importing.

smuggling (noun)	importation (noun)
secretly importing prohibited goods or goods on which duty is due	the commercial activity of buying and bringing in goods from a foreign country
	commodities (goods or services) bought from a foreign country