nat·u·ral·ize 
(năchər-ə-līz′, năchrə-)
(năchər-ə-līz′, năchrə-)v. nat·u·ral·ized, nat·u·ral·iz·ing, nat·u·ral·iz·es
v.tr.
1. To grant full citizenship to (one of foreign birth).
2. To adopt (something foreign, such as a custom or a word from another language) into general use.
3. To introduce and establish (a species) in an environment to which it is not native: European birds that became naturalized in North America.
4. To explain (an occurrence, for example) by natural causes in contrast to supernatural causes.
v.intr.
To become naturalized or acclimated.
nat′u·ral·iza·ble adj.
nat′u·ral·i·zation (-lĭ-zāshən) n.