The Orient refers to a region on the planet Earth, located in the Eastern Hemisphere continent of Asia. It was the home of Asian peoples.
History and specifics
Spock's quarters on board the USS Enterprise, although decorated in the Vulcan style, appeared to be vaguely Oriental in design. (TOS - Star Trek 3 novelization: Amok Time, TOS novel: Spock Must Die!)
Karate originated from the Orient. (TAS - Log Six novelization: Albatross)
Jonathan Archer compared the Rigel Trade Complex on Rigel X to an alien version of an Oriental bazaar. (ENT novelization: Broken Bow)
Starbase 7 resembled a cross between an Oriental bazaar and a zoo run amok. (TOS novel: Death's Angel)