skin

The outer protective layer of the body of any animal, including of a human.

How to use

In formal contexts, such as medical or scientific writing, the word 'skin' is often used to refer to the outermost layer of the body, while in more casual conversations, people may use it to describe a person's complexion or appearance. For example, 'Her skin looked radiant after the vacation' is a common expression, but in a medical context, 'The skin on her hands was severely dry' would be more accurate. It's worth noting that the phrase 'to get under someone's skin' is a common idiom, but it's often misused by learners, who might say 'I got under her skin' instead of 'She got under my skin'.