Plural of mutt; mixed-breed dogs or, informally, foolish people.
American slang from early 20th century, possibly shortened from 'muttonhead' (stupid person). Originally derogatory for both dogs and people, the term has been somewhat reclaimed in recent decades as mixed-breed dogs are recognized for their health benefits and unique characteristics.
Ironically, 'mutts' are often healthier than purebreds due to hybrid vigor - the biological advantage of genetic diversity. What was once a term of derision has become a badge of honor among dog lovers who appreciate the unique personalities and robust health of mixed breeds!
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