pentagon

In geometry terms the difference between pentagon and star

is that pentagon is a polygon with five sides and five angles while star is a concave polygon with regular, pointy protrusions and indentations, generally with five or six points.

As a verb star is

to appear as a featured performer or headliner, especially in an entertainment program.

As nouns the difference between taxonomy and pentagon

is that taxonomy is the science or the technique used to make a classification while pentagon is a polygon with five sides and five angles.

As a proper noun Pentagon is

the headquarters of the United States of America's Department of Defense.

As a noun pentagon

is pentagon.

As an adverb pentagonally is

in the form of a pentagon; with five angles.

As nouns the difference between pentagon and pentagrid

is that pentagon is pentagon while pentagrid is (mathematics) a tiling of the hyperbolic plane with regular pentagons.

As a noun pentagon

is pentagon.

As an adjective subpentagonal is

(anatomy|botany) having five sides, but not forming a regular pentagon.

As nouns the difference between pentagon and icosidodecahedron

is that pentagon is pentagon while icosidodecahedron is a semiregular polyhedron with twelve faces that are regular pentagons and twenty that are equilateral triangles.