Is Guam a valid Scrabble word?

Could you please clarify if the word "Guam" is indeed a legitimate option to play in a game of Scrabble? It's quite an uncommon word, and I'm curious to know if it adheres to the official Scrabble word list standards. Could you verify its validity, taking into account the usual constraints of Scrabble, such as letter combinations and word length? I'm particularly interested in whether this word would score any points if used in a game.