cone of shame 

The plastic cone-shaped protective collar that a veterinarian puts on a dog or cat to prevent them from licking or pawing at an area of their body while it's healing from an injury or surgery. Also referred to as an Elizabethan collar (or e-collar), because of its similarity to the collars worn in Elizabethan dress.

Sherpa isn't enjoying being with the other dogs at the dog park today. You can tell he's embarrassed wearing the cone of shame that the vet put on him after his injury.

cone of shame by Casa de mil suenos August 13, 2017

Cone of Shame 

A comical piece of headwear that one usually wears when put into a shameful situation. The cone of shame brings attention to the said person and makes the said person feel guilty.

Brice ate so much turkey that he had left none for the rest of his family; for the rest of the week, Brice had to wear the cone of shame.

Cone of Shame by Zeniers November 27, 2009

Cone of Shame 

Dunce cap. A cone with a big ''D'' written on the front given out if you are a dunce

No, Nigel. That's not even close to being right. Now you must wear the dunce cap (cone of shame)

Cone of Shame by Bareechkle September 5, 2016