No. A sphere is curved with no corners and it is not flat.
A circle could also be considered curved with no corners but flat.
cylinder
Curved and flat faces.
fwf
Any curved shape such as a circle, an ellipse, an oval, a wriggly line - as long as it does not have any corners.
sphere
A cylinder.
Irregular shape is the term given to an object which has 1 flat side, 1 curved side, no corners but has curved edges.
Well, if you think about it, a baseball diamond fits the description perfectly!
curved
sphere
A curved line.
A sphere.
There isnt one
A hemisphere
a circle
A circle....
Assuming there are no curved sides, it is a decahedron. It is likely to be an octagonal prism but there may be other configurations.