U+23A7 "⎧" Left Curly Bracket Upper Hook Unicode Character

U+23A7 "⎧" Left Curly Bracket Upper Hook is a typographic symbol belonging to the Miscellaneous Technical block, specifically designed as a component for constructing large, multi-line curly brackets in mathematical or technical typesetting. It represents the top segment of a left-opening brace, featuring a small horizontal hook extending downward from the upper portion to seamlessly connect with the middle and lower parts of the bracket. This character is often used in combination with other bracket fragments, such as the left curly bracket middle piece and lower hook, to create extensible braces that scale vertically for enclosing stacked expressions, equation systems, or sets in plain text environments where automatic bracket stretching is unavailable.