I was looking at the definitions of "nerve" given in Lexico nee ODO, and I got two definitions of it that are quite the opposite of each other:
one's steadiness and courage in a demanding situation.
"an amazing journey which tested her nerves to the full"
feelings of nervousness.
"his first-night nerves soon disappeared"
This pair of definitions and their respective examples above completely oppose each other, methinks.
How does something like this happen? Unless I have misinterpreted these definitions, how can a word have two definitions that make opposing claims to each other?