Keyhole shape, a round top over a narrow slot, like a lock opening; legacy computing symbol.
U+1CEB0HORIZONTAL ZIGZAG LINEU+1CEB2OLD PERSONAL COMPUTER WITH MONITOR IN PORTRAIT ORIENTATIONU+1CEAFLOWER HALF RIGHT ONE QUARTER BLOCKU+1CEB3BLACK RIGHT TRIANGLE CARETU+1CEAELOWER THREE QUARTERS RIGHT ONE QUARTER BLOCKU+1CEADUPPER THREE QUARTERS RIGHT ONE QUARTER BLOCKU+1CEACUPPER HALF RIGHT ONE QUARTER BLOCKU+1CEABRIGHT HALF UPPER ONE QUARTER BLOCKU+1CEAARIGHT THREE QUARTERS UPPER ONE QUARTER BLOCKU+1CEA9LEFT THREE QUARTERS UPPER ONE QUARTER BLOCKU+1CEA8LEFT HALF UPPER ONE QUARTER BLOCKU+1CEBAFRAGILE SYMBOL695 characters in the Symbols for Legacy Computing Supplement Unicode block, from number 687.