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Is there a formal name for an irregular polygon that has 1 or more holes or cutouts in it? I've heard it refered to as a "swiss cheese polygon" or a "Donut polygon". Is this even strictly a polygon?

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It is not a polygon, since by definition, a polygon is a plane figure bounded by a closed curve. – M Turgeon Aug 29 '12 at 17:13
I don't think there's a standard name. Polygon with holes (958 hits on Google Books) is the usual term; rarer terms include donut/doughnut polygon (70 hits), swiss-cheese polygon (6 hits), and non-simply-connected polygon (1 hit). – Gareth Rees Aug 29 '12 at 17:26
@MTurgeon I think it should be prohibited by definition too, but "plane figure" doesn't seem to exclude holes, nor does "bounded by a closed piecewise linear curve". – rschwieb Aug 29 '12 at 17:27
There might be a term based on the fact that these are all the (connected?) planar objects that can be broken up into triangles. – Thomas Andrews Aug 29 '12 at 18:32
@rschwieb Maybe I should have phrased it in the following way: "the plane figure of 'maximal area' bounded by a closed curve", although this is not quite precise. – M Turgeon Aug 29 '12 at 18:38

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