In Scrabble, can you look up words in a dictionary?

The rules of official Scrabble do not allow you to consult a word reference before moving. Depending on where you play, you can lose your turn if a word turns out to be valid. North American clubs and tournaments use a rule known as the ‘double challenge,’ allowing the challenger to lose their turn if they lose their turn twice. This is also the rule stated on the official Hasbro Scrabble website, the North American owner of Scrabble. There is no loss of a turn in most official Scrabble games played outside North America. However, the challenger may lose 5 or 10 points in some tournaments if the challenge is incorrect.