Was heißt »Ersteigung« auf Englisch?

Das Substantiv »Ersteigung« lässt sich wie folgt von Deutsch auf Englisch übersetzen:

Antonyme

The next morning it was blowing a gale, and we had to delay the ascent.
When I looked up, I saw a huge spider climbing the wall.
I saw Tom climbing in through the window.
I saw Tom climbing up to the window.
He liked climbing trees as a kid.
I dreamt I was a cat climbing a tree. I wonder what that's supposed to mean?
There's a new climbing frame in the playground.
We were climbing a steep slope.
I kept climbing upwards.
He kept climbing.
Tom likes climbing mountains.
Alain Robert, known as the "French Spiderman", was arrested after climbing a high-rise building in Frankfurt without permission.
Mountain climbing is a lot of fun.
It isn't much fun to go mountain climbing by yourself.
Monkeys are good at climbing.
Some people escaped the water by climbing onto the top of their homes while waiting to be rescued by helicopter.
I'm interested in mountain climbing.
Why do you think Tom enjoys climbing trees so much?
I don't like climbing ladders.
Tom says he saw someone climbing over the fence.