Playing word games makes vocabulary stick by using active recall, which means...

https://wiki-cafe.win/index.php/Why_Do_I_Remember_Words_from_Games_But_Not_from_Lists%3F

Playing word games makes vocabulary stick by using active recall, which means you practice remembering words instead of just reading them. For example, when you guess the word "deal" in a game, your brain connects it with its meaning and spelling