crime syndicate vs gangdom

crime syndicate and gangdom both are nouns.

Word	Noun	Adjective	Verb	Adverb
crime syndicate	Yes	No	No	No
gangdom	Yes	No	No	No

As nouns, gangdom is a hypernym of crime syndicate; that is, gangdom is a word with a broader meaning than crime syndicate:

crime syndicate: a loose affiliation of gangsters in charge of organized criminal activities
gangdom: underworld organizations

Other hypernyms of crime syndicate include gangland, organized crime.

crime syndicate (noun)	gangdom (noun)
a loose affiliation of gangsters in charge of organized criminal activities	underworld organizations