smuggling vs importing

smuggling and importing both are nouns.

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

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

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

Other hypernyms of smuggling include importation.

smuggling (noun)	importing (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