no shape
circle
One.
Balls
A one sided shape (ignoring the poor grammar) is a line. Is that what you wanted?
a line
A two-dimensional shape with one curved side and four straight sides can be created, but there is not specific name for such a shape.
hectagon
A shape with one side
A shape with three linear sides and one curved side can be drawn, but such a shape has no specific name.
its a shape
No shape does. However, a line and/or line segment is "one-sided".
If you are referring to a shape, then a semi-circle would be the most likely shape that contains one straight side and one curved. Take a look at a protractor, it's a semi-circle.
A sphere
A blob.
a line
A Moebus strip.