地区【ちく】
district, section, sector
区域【くいき】
limits, boundary, domain, zone, sphere, territory, area (e.g. in programming languages)
区間【くかん】
section (of track, etc.), segment, dimension, interval
区【く】
ward, borough, city (in Tokyo), district (e.g. electoral), section, zone (e.g. postal)
区別【くべつ】
distinction, differentiation, classification
区分【くぶん】
division, section, demarcation, partition, segmentation, subdivision, (traffic) lane, compartment, classification, sorting
区画【くかく】
division, section, compartment, block, plot, lot, partition, boundary
区役所【くやくしょ】
ward office, council (regional)
区切る【くぎる】
to divide, to separate, to partition, to demarcate, to delimit, to mark off, to punctuate, to mark off (with a comma), to insert pauses (between words or phrases when reading aloud), to space one's words