Talking about Geometry: English Vocabulary List

(geometry) a solid or hollow shape with two circular bases at each end and straight parallel sides

"A cylinder has two bases."

"The engineer designed a hollow cylinder with a specific radius and height for the structural component."

(geometry) a closed shape with six straight sides and six angles

"A hexagon has six sides."

"A hexagon is a polygon with six sides and six angles, commonly found in nature."

a type of triangle that has two sides of equal length and two angles of equal measure

"An isosceles triangle has two equal sides."

"An isosceles triangle has two sides of equal length and two equal angles opposite those sides."

(geometry) a polygon consisting of eight straight sides and eight angles

"An octagon has eight sides."

"The stop sign is a familiar example of an octagon, a polygon with precisely eight equal sides and angles."

in geometry, a pattern or shape that exhibits a twisting or spiraling motion, often characterized by continuous, curved lines forming a rotational or helical design

"Swirl is a spiral."

"The artist painted a beautiful swirl of colors on the canvas, creating a dynamic effect."

a point where two or more lines, edges, or rays meet to form an angle, or the point at which the sides of a polygon intersect

"The vertex is here."

"The vertex of the pyramid is the single point at the apex where all the triangular faces meet."

(geometry) a closed plane curve that has two focal points

"An ellipse is oval."

"The orbit of a planet around the sun is not a perfect circle but rather an ellipse with the sun at one focus."

(geometry) a flat shape consisting of three or more straight sides

"A polygon has sides."

"A polygon is a closed two-dimensional shape formed by straight line segments, such as a triangle or a square."

a geometric shape with five angles and five straight sides

"A pentagon has five."

"The United States Department of Defense headquarters is famously known as the Pentagon due to its five-sided geometric shape."

(geometry) a flat polygon with ten straight sides and ten angles

"A decagon has ten."

"A decagon is a polygon characterized by having exactly ten straight sides and ten interior angles."

(geometry) a flat shape consisting of nine straight sides and nine angles

"A nonagon has nine."

"A nonagon is a geometric figure that possesses nine straight sides and nine corresponding angles."

a seven-sided plane shape consisting of seven line segments or edges that meet at seven interior angles

"A heptagon has seven sides."

"The architectural design featured a unique heptagon shape for the central courtyard, creating an unusual space."

a three-dimensional shape similar to a stretched or compressed sphere

"Ellipsoid is stretched sphere."

"The planet Earth is not a perfect sphere but rather an ellipsoid due to its rotation."

a three-dimensional geometric shape with six rectangular faces, resembling a box or a rectangular prism

"The box is a cuboid."

"A standard brick is a perfect example of a cuboid, a rectangular prism with six flat faces."

(geometry) a round 3D shape like a ball that is slightly flattened at the top and bottom points

"Spheroid is slightly flat."

"Scientists describe Earth as a spheroid because it is slightly flattened at both poles."

a solid shape made of flat sides that fit together along their edges

"A cube is a polyhedron."

"A cube is the most common example of a polyhedron that students study in math class."

a three-sided polygon

"A trigon has three sides."

"In geometry, a trigon is simply another term for a triangle, a polygon with exactly three sides."

(geometry) a flat star-shaped figure with six points that can be formed by making equilateral triangles on each side of a regular hexagon

"A hexagram is a six-pointed star formed from two overlapping triangles."

"The geometric hexagram is a six-pointed star formed by two overlapping equilateral triangles."

an angle that measures either less or more that 90 degrees

"An oblique angle is not right."

"An oblique angle is any angle that is not a right angle or a straight angle."

an angle that measures greater than 180 degrees but less than 360 degrees

"The angle is a reflex angle."

"A reflex angle is an angle greater than 180 degrees but less than 360 degrees."

a straight line from one side of a round object, particularly a circle, passing through the center and joining the other side

"The diameter of the circle is ten centimeters."

"The diameter of the tree trunk was so large that two people could not wrap their arms around it."