noun
closed caption
Refers to captions that can be turned on or off by the viewer, as opposed to open captions that are always visible. Used in broadcasting and video contexts.
この番組はクローズドキャプションに対応しています。
This program supports closed captions.
Variant with interpunct, sometimes used for clarity.
字幕 is a general term for subtitles, often used for foreign-language translation, while クローズドキャプション specifically refers to captions for the hearing impaired that can be toggled on/off.
オープンキャプション are always visible captions, whereas クローズドキャプション can be turned on or off by the viewer.
Borrowed from English 'closed caption'.