verb

• (transitive) To grant citizenship to someone not born a citizen.
  "Pakche was destroyed and five years later, Kokuryo was also swept away by T’ang and Silla. T’ang set up An-tontu-hu-fu (Government headquarters) at P’ing jang to rule the former territories of Pakche and Kokuryo. Many refugees from these destroyed states came to Japan and became naturalized as Japanese."
• (transitive) To acclimatize an animal or plant.
  "Its wearer suggested that pears and peaches might yet be naturalized in the New England climate."
• (transitive) To limit explanations of a phenomenon to naturalistic ones and exclude supernatural ones.
• (linguistics, transitive) To make (a word) a natural part of the language, using the native homologue of each phoneme (and often for each morpheme) of the imported word (e.g., native inflections).
  "In English, foreign words are typically written in italics until they are naturalized."