Crossword Clue:

plane figure with eight sides

AnswerCrossword Clue
NGONFigure with x sides.
DECAGONFigure with 10 sides
NONAGONFigure with nine sides.
HEPTAGONFigure with seven sides
SCALENETRIANGLEFigure with three unequal sides
TRAPEZOIDFour-sided figure with two parallel sides.