The meaning of the Acronym DUMB is...

DUMB is

• Doorknob Under My Bed

More Meanings For DUMB:

• Doorknob Under My Bed
• Deep Underground Military Bunker
• Deep Underground Military Bunker
• Deliberately Underachieving Makeshift Ballteam

DUMB is also in:

• Adults
• Military
• Sports
• US Government