Is REKEY a Wordle Word?

Yes. REKEY is a valid Wordle word.

It is not on the Wordle answer list, so it is unlikely to be a daily answer.

What does REKEY mean?

To enter information into a device, such as a keyboard or keypad, after it has been done at least once before.“She had to rekey the security code.”
To modify (a lock or its cylinder) to change which keys will open it.
To change the key or tenor of; to reframe.

Definition from Wiktionary, available under the CC BY-SA license.

Starter word rating: WeakIn the top 67% of all valid Wordle words for testing common letters.
Vowels: E
Unique letters: 4 of 5Repeats E
Common letters: R, E

Letter ratings use how often each letter appears in Wordle answers.

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