Is THUMB a valid Scrabble word?

Yes. THUMB is valid in Collins Scrabble Words 2024, the word list used for Scrabble in the UK.

What THUMB means

• noun - The shortest and thickest digit of the hand that for humans has the most mobility and can be made to oppose (moved to touch) all of the other fingers.
• verb - To touch or cover with the thumb.

Definitions come from Wiktionary via kaikki.org, shortened to fit, and are used under CC BY-SA 4.0.

Gramlet is a daily word game played with the same Collins list. Play today's board.