noun
subarea; subregion; portion
Technical term used in computing and related fields to refer to a part of a larger area or domain, such as a subregion of an image or a portion of memory.
画像の部分領域を切り取って拡大する。
Cut out and enlarge a subregion of the image.
メモリの部分領域にデータを書き込む。
Write data to a portion of memory.
領域 is a general term for area, domain, or field, while 部分領域 specifically refers to a subarea or portion within a larger domain, often in technical contexts.
Compound of 部分 (ぶぶん, 'part') and 領域 (りょういき, 'area, domain'). The exact historical derivation is uncertain, but the word is formed from standard Sino-Japanese elements.