noun
record boundary character
Technical term in computing for a character that marks the boundary between records in a data stream or file.
CSVファイルでは、改行が記録境界文字として使われることが多い。
In CSV files, a newline is often used as the record boundary character.
Compound of 記録 (record) + 境界 (boundary) + 文字 (character). A straightforward technical term.