noun
selected area; selection region
Computing term for a highlighted or chosen area in a user interface, such as a text selection or a region in an image editor.
選択領域をコピーして別のファイルに貼り付けます。
Copy the selected area and paste it into another file.
Similar computing term for a selection range; 選択領域 often implies a two-dimensional area, while 選択範囲 can be more general.
Compound of 選択 (selection) and 領域 (area, region). A straightforward technical term.