It's not a literal phrase, it's more like a saying. It means that your stubborn or it's hard to change your mind. Once your set on something you do it. That's what I think I being thick skinned.
It means toughen up and don't let it bother you. Example if someone is saying means things just ignore it and let it roll off your back.
pachyderma
The physical characteristics of hippos include protruding eyes, long curved front teeth, thick, brownish-gray skin, 4 webbed toes, Short legs, and a 5 feet height. Physical characteristics of a hippo include thick skin, four toes on each foot, bulky body and short, stumpy legs.
Webbed feet, slimy body thick fur leathery skin
It is the skin of the rhino that is 5 cm thick. The skin of the rhino and hippopotamus is usually between 1.5cm and 5cm thick.
buffalo's skin is 1.562cm thick
buffalo's skin is 1.562cm thick
When they are in the cold water, the thick skin heats them up.
it is thick
They are only one cell thick and have very thin walls, to allow nutrients and oxygen to diffuse out of them.
Skin! The skin of a rhinoceros is 18-20 mm thick. In some parts it is 45 mm.
the thick scaly skin would be strong to defend against attacks
1.5-5 cm thick
On average, 1.5 millimeters thick