to make something final or complete, bringing it to its finished state so no more changes can be made.
From 'final' (from Latin 'finalis', meaning 'of the end') + '-ize' (a suffix meaning 'to make' or 'to cause to be'). This is a relatively modern word formation from the 20th century.
Interestingly, 'finalize' didn't appear in most dictionaries until the 1950s even though it seems like a simple word—people were happier saying 'make final' or 'conclude' for centuries before this verb form became standard.
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