1) Ecological process 2) French word used in English 3) Naturalization 4) Naturalness 1) Naturalization 
[biology] In biology, naturalization is any process by which a non-native organism spreads into the wild and its reproduction is sufficient to maintain its population. Such populations are said to be naturalized. Some populations do not sustain themselves reproductively, but exist because of continued influx from elsewhere. Such a non-susta...
To naturalise a foreign national as French is to grant them the status of full French citizenship. Naturalisation by a decision of the public authorities may only be granted to a foreigner having a usual place of residence in France for the five years prior to filing the application (except in the cases of reduction or waiver of the five-year waiti...
The official process that someone of foreign birth goes through to become a citizen of another country.
The process whereby adults who are not British may apply for British Citizenship.