* Lack of the ability to speak. This is the original and most literal meaning of the word, often used to describe someone who cannot speak due to a physical disability or a medical condition.
* Lack of intelligence or understanding. This is a more common and often offensive use of the word, implying someone is stupid or lacking in intelligence.
If you were looking for a specific meaning related to "dumness," it's important to clarify the context or provide more information so I can help you further.