Simple past tense and past participle of dumb.(verb)
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Use "dumbed" in a sentence
"He gave us a beautiful description in Spanish, dumbed down for me, I believe of how they are made and what they mean."
"But we shouldn’t use what I call the dumbed-down new evening news model to decide what’s up (one side talks, the other side talks, you conclude with “there’s two sides, I guess we’ll never know”)."
"And if so, you should know that WoW does an excellent job of providing their playerbase with what I like to call dumbed-down game mechanics."