[1] : WordNet (r) 2.0

concave polygon
     n : a polygon such that there is a straight line that cuts it in
         four or more points ant: convex polygon
see also:
convex polygon 

Concave Polygon >> C Words
Concave Polygon, definition of term: Concave Polygon
concave+polygon_pag1.html

Polygon >> P Words
Polygon, definition of term: Polygon
polygon_pag1.html

Concave >> C Words
Concave, definition of term: Concave
concave_pag1.html

Concave Lens >> C Words
Concave Lens, definition of term: Concave Lens
concave+lens_pag1.html

Regular Polygon >> R Words
Regular Polygon, definition of term: Regular Polygon
regular+polygon_pag1.html

Convex Polygon >> C Words
Convex Polygon, definition of term: Convex Polygon
convex+polygon_pag1.html