Annoyed with lag: 60 minutes upset one with thick skin (10)

I believe the answer is:

rhinoceros

I'm a little stuck... Click here to teach me more about this clue!

'skin' is the definition.
The definition and answer can be both animals as well as being singular nouns.
Maybe you can see a link between them that I can't see?

I don't understand the rest of the clue.

Can you help me to learn more?

(Other definitions for rhinoceros that I've seen before include "Horned mammal" , "Ionesco's work" , "Thick-skinned beast" , "Big game" , "Large horned animal" .)

I've seen this clue in The Telegraph.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.