Geometric shape
(Other definitions for cube that I've seen before include "Square-faced solid" , "Form of chiller" , "Six-sided body" , "Power of three" , "Raise to the third power" .)
'geometric shape' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for cone that I've seen before include "it may hold ice-cream" , "Ice-cream cornet" , "Geometric solid - fruit of pine" , "Volcano peak" , "Ice cream holder" .)
'geometric shape' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for circle that I've seen before include "Perfectly round plane figure" , "Theatre's upper tier" , "Clique; loop" , "Cycle - enclosure" , "Theatre seating tier" .)
(Other definitions for square that I've seen before include "It has four equal sides and four right angles" , "Old-fashioned - fix" , "See 19" , "bashed by soldiers in training?" , "Rectangle with equal sides" .)
(Other definitions for octagon that I've seen before include "Figure of many sides" , "Eight-sided figure" , "Eight sided figure" , "with eight angles" , "An eight-sided polygon" .)
(Other definitions for trapezoid that I've seen before include "Figure" , "Type of quadrilateral" , "Form of quadrilateral" , "Prize toad (anag.)" .)