GIGANTISM

Yes, GIGANTISM is a Scrabble word!

Letter values in Scrabble US: G 2, I 1, G 2, A 1, N 1, T 1, I 1, S 1, M 3.G 2 · I 1 · G 2 · A 1 · N 1 · T 1 · I 1 · S 1 · M 3

Is it a valid word?

• Scrabble US: valid, 13 points.Scrabble USYour dictionary · Change (go to the dictionary switch)Valid · 13 points
• Scrabble UK: valid, 13 points. Make Scrabble UK your dictionary.Scrabble UKYour dictionary · ChangeValid · 13 points
• Words with Friends: valid, 17 points. Make Words with Friends your dictionary.Words with FriendsYour dictionary · ChangeValid · 17 points