What is the meaning of ☑?

Indicates an item (especially in a list) that is fulfilled or dealt with, e.g., products in a grocery list that were already bought.

Indicates one's preference or vote. Sometimes, a ballot (☐) can be filled with a checkmark: ☑.

Indicates correctness (with the exception of some languages, in which it is used with the opposite meaning).

Used as a tally mark.

Source: wiktionary.org

See also