uphill

Refers to a very difficult struggle where success is not certain.

A long and difficult effort to achieve something.

A very difficult piece of work that needs to be done.

A difficult contest or effort against strong opposition.

A steep ascent, either literally on a hill or metaphorically representing a difficult process.

The final part of a race or competition that is on an upward slope, making it more difficult.

A surface of which one end is at a higher level than another.

A technical term for an upward slope, especially for roads or railways.