Having a slope, it's not exactly level (5)
I believe the answer is:
bevel
'exactly level' is the definition.
The definition and answer can be both man-made objects as well as being singular nouns.
Maybe they are linked in a way I don't understand?
I cannot understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for bevel that I've seen before include "Two surfaces that meet at an angle different from 90 degrees" , "Sloping edge or chamfer" , "Slanting surface" , "Tool for making a sloping edge on a piece of wood" , "Inclination of a surface" .)