Synonyms for Region (same or very similar meaning)
WordNet sense 1 (the approximate amount of something (usually used prepositionally as in `in the region of')):
neighborhoodWordNet sense 2 (the extended spatial location of something):
partWordNet sense 3 (a knowledge domain that you are interested in or are communicating about):
domain, realmWordNet sense 4 (a part of an animal that has a special function or is supplied by a given artery or nerve):
areaFrom the ODE community, based on WordNetadd/edit