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A demonym (/ˈdɛmənɪm/; from Ancient Greek δῆμος (dêmos) 'people, tribe', and ὄνυμα (ónuma) 'name') or gentilic (from Latin gentilis 'of a clan, or gens') is a word that identifies a group of people (inhabitants, residents, natives) in relation to a particular place. Demonyms are usually derived from the name of the place (hamlet, village, town, city, region, province, state, country, and continent). Demonyms are used to designate all people (the general population) of a particular place, regardless of ethnic, linguistic, religious or other cultural differences that may exist within the population of that place...
...demonyms are semantically different from ethnonyms (names of ethnic groups). In the English language, there are many polysemic words that have several meanings (including demonymic and ethnonymic uses), and therefore a particular use of any such word depends on the context. For example, the word Thai may be used as a demonym, designating any inhabitant of Thailand, while the same word may also be used as an ethnonym, designating members of the Thai people...
Often, demonyms are the same as the adjectival form of the place, e.g. Egyptian, Japanese, or Greek. However, they are not necessarily the same, as exemplified by Spanish instead of Spaniard or British instead of Briton...
Several linguistic elements are used to create demonyms in the English language. The most common is to add a suffix to the end of the location name, slightly modified in some instances. These may resemble Late Latin, Semitic, Celtic, or Germanic suffixes, such as -(a)n, -ian, -anian, -nian, -in(e), -a(ñ/n)o/a, -e(ñ/n)o/a, -i(ñ/n)o/a, -ite, -(e)r, -(i)sh, -ene, -ensian, -ard, -ese, -nese, -lese, -i(e), -i(ya), -iot, -iote, -k, -asque, -(we)gian, -onian, -vian, -ois(e), or -ais(e).