People who are native to or inhabitants of California; residents of the state of California.
From California (the state) plus -ian suffix (meaning inhabitant or native of) plus the standard English plural -s. The term emerged in American English in the 19th century as California became a defined political entity.
Place-name demonyms (the words for people from places) are wildly inconsistent across English—we have Californians but New Yorkers, Londoners but Parisians, showing how language sometimes defies logical patterns and just follows historical accident.
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