⬛ · Symbols › Shapes · Emoji 0.6 (2010)
⬛ is a solid black square, one of the oldest emojis, around since 2010.
In Wordle results shared from dark mode, ⬛ is a letter that isn't in the word. In emoji art it's the outline and the shadow, and the background that makes the colors pop on a dark screen.
Paint with ⬛ in the emoji art editor, or turn any photo into emojis with the image to emoji converter.
U+2B1B⬛\2B1B\u{2B1B}\U00002B1B%E2%AC%9B← 🟫 Brown Square · ⬜ White Large Square → · Symbol emoji library