noun. a black-tipped plug clogging a pore of the skin.
1. Verb, 3rd person singular present Schnauzer comedo syndrome, unique to the breed, is a type of canine acne. 2. Noun, singular or mass Oxygen in the air reacts with the sebum and darkens it, forming a dark plug of matter called a blackhead or open comedo. 3. Adjective If the black spots stayed put throughout the bath, appear to be scabs or are accompanied by bumps on the skin, your dog probably has schnauzer comedone syndrome also known as comedo syndrome.