THUMBNAIL

Yes, THUMBNAIL is a Scrabble word!

Letter values in Scrabble US: T 1, H 4, U 1, M 3, B 3, N 1, A 1, I 1, L 1.T 1 · H 4 · U 1 · M 3 · B 3 · N 1 · A 1 · I 1 · L 1

Is it a valid word?

• Scrabble US: valid, 16 points.Scrabble USYour dictionary · Change (go to the dictionary switch)Valid · 16 points
• Scrabble UK: valid, 16 points. Make Scrabble UK your dictionary.Scrabble UKYour dictionary · ChangeValid · 16 points
• Words with Friends: valid, 20 points. Make Words with Friends your dictionary.Words with FriendsYour dictionary · ChangeValid · 20 points