Is “Thumb” a Scrabble word?
Yes
THUMB
Valid in at least one Scrabble dictionary
Valid in these dictionaries
SOWPODS / CSW
Scrabble UK & International
TWL / NWL
Scrabble North America
Large English Dictionary
General English word list
Meaning of Thumb
/θʌm/
noun
1.The short thick 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.
2.The part of a slider that may be moved linearly along the slider.
3.A thumbnail picture.
“2001, "Gary", Wanna See Porn? Take a Look At These (Free Expandable Thumbs) - CLICK HERE (on newsgroup alt.sex.services)”
Synonyms: digit I, first digit, pollex, thumby
verb
1.To touch or cover with the thumb.
“to thumb the touch-hole of a cannon”
2.(with through) To turn the pages of (a book) in order to read it cursorily.
“I thumbed through the book and decided not to bother reading it all.”
3.(travel) To hitchhike
“So I started thumbin' back east, toward my hometown.”
Synonyms: browse, leaf, page, peruse