If they are straight sides, then a polygon. Otherwise, simply "a closed plane figure with 3 or more sides".
There is no specific name for "12 or more" sides. A 12 sided plane figure is a dodecagon. More generally, a plane figure bounded by 3 or more sides is a polygon.
quadlateral
None. A figure must have more sides than angles.
It is a polygon that is a closed plane figure with 3 or more straight lines.
Yes and it has 3 or more sides
2 dimensional (plane) figures can have three or more straight edges as sides. 3 dimensional (solid) figures can have four or more plane sides (faces). They can have fewer sides if the sides are not straight.
A polygon is a plane figure with 3 or more straight sides and angles. A plane figure is a flat enclosed figure made of straight lines, curved lines, or both.
Polygon
A polygon.
A 12-sided polygon is called a dodecagon. See this website for more names: http://mathforum.org/dr.math/faq/faq.polygon.names.html a plane figure 12 sides
a figure, esp. a closed plane figure, having three or more, usually straight, sides.