Omsk vs urban center

Omsk and urban center both are nouns.

Word	Noun	Adjective	Verb	Adverb
Omsk	Yes	No	No	No
urban center	Yes	No	No	No

Omsk (noun)	urban center (noun)
a city in the Asian part of Russia, Russia's seventh-largest city	a large and densely populated urban area; may include several independent administrative districts