Code point
U+25DB
Glyph appearance depends on your fonts.
U+25DB
SoU+25DB LOWER HALF INVERSE WHITE CIRCLE is a Unicode 16.0.0 character in the Other Symbol category. It belongs to the Geometric Shapes block.
Choose the representation you need, then copy its value.
U+25DB
9691
◛
◛
E2 97 9B
25DB
000025DB
%E2%97%9B
\u25DB
\u25DB
\u25DB
\25DB