by Doug
(California)
Using a dictionary to check words before or after you play them or checking the validity of an opponents word(s) greatly undermines the integrity of the game.
Instead, write down the words you are unsure of and check them after the game. You can even go as far as writing down your rack combinations and using an available online anagram generator, find out what words may have been available to you.
You'll probably retain that information better using that method and can sleep well knowing you played the game honestly :-)