What is tarnishment?
Tarnishment is one of the two ways a famous trademark can be diluted. Specifically, tarnishment occurs where someone uses a mark which causes the famous mark to be linked with inferior quality products or seen in an unwholesome context. For example, if an adult website used the MICKEY MOUSE trademark, while consumers would not likely be confused and think that Disney Enterprises runs the website, it would still serve to portray Disney’s mark in an unwholesome context. As such, Disney could prevent this usage under the antidilution statues.
The other way a famous trademark can be diluted is through blurring.