Having a dirty or shabby appearance, often due to neglect or disease. The mangy dog wandered the streets, its fur patchy and unkempt.
In poor condition; squalid or run-down. The mangy old sofa was covered in stains and had springs poking through the fabric.
Affected with mange, a contagious skin disease that causes itching and loss of hair in animals. The rescue center treated a mangy cat whose skin was raw from constant scratching.
Informal: mean, contemptible, or despicable. Some mangy thief ran off with my bicycle.