Here in this lesson, we will study some important geometric shape names in English. It is important to know that the words Hexagonal, Rhombus, and Circle are very common in competitive exams. So it is a must to have a good grip on these basic shape names.

**List of Geometric Shape Names**

**Circle**

Circle is the line which is drawn from the middle of a circle that touches its circumference equally. In geometry, circle is considered as a set of points that are equidistant from a point.

**Square**

It is a four sided plane figure in which all the sides are of equal length and all the angles are of right size. In other words, square is rectangle that have four equal sides.

**Rectangle**

It is a four sided plane figure in which two pairs of opposite sides are of equal length and all the angles between them are right angle. In other words, square is rectangle that have only two sets of parallel sides.

**Triangle**

A triangle is a planar shape with three line segments which enclose a space outside it. A triangle must have 3 vertices or corners. There are 6 types of triangles namely equilateral, isosceles, right angled, obtuse, acute and scalene.

**Parallelogram**

A parallelogram is a four sided plane figure in which opposite sides are parallel to each other and all the angles between them are right angles.

**Rhombus**

It is a four sided plane figure in which all the sides are equal in length and all the angles between them are of right size. It has two sets of parallel sides that are perpendicular each other. It is also known as Diamond Shape .

**Trapezium **

It is quadrilateral with only one pair of parallel sides that are called bases. The line segment joining the mid-points of the non-parallel sides is called a lateral by both bases.

**Exagonal **

A regular exagon has equal sides and all the angles are right angle. You can remove any number of points from a regular exagon and still get a other regular exagons as it is made up of indivisible lines. In other words, an exagon is a closed figure constructed from 3 line segments by connecting each end point to every other end point on those lines.

**Pentagon**

It is a plane figure with 5 sides. It has 5 vertices or corners.

**Hexagon**

It is a plane figure with 6 sides. A regular hexagon has all the angles of equal size and all the side lengths are equal length. In other words, it is a closed figure constructed from 3 line segments by connecting each end point to every other end point on those lines.

**Heptagon **

It is a seven sided plane figure in which all the angles are right angle and its shape resembles that of an egg. It can also be called as septagon . An heptagonal polygon is a polygon whose seven sides are congruent and the included angle at each vertex measures 110o .

**Octogon **

An octogan has 8 sides. It looks like a stop sign with straight arms on each side equally spaced apart from one another.

**Nonagon **

A nonagon is also called as enneagon . It is an nine-sided polygon or 9-gon .It has nine vertices and of course nine edges of equal length. It can be constructed by joining the midpoints of the sides of hexagon.

**Decagon **

It is a ten sided figure in which all the angles are right angle and its shape resembles that of an egg. A regular decagon has all the sides equal, and all its interior angles measure 108o . In other words, it can be said as a ten sided polygon or 10-gon.

**Dodecagon **

It is a 12-sided figure in which all the angles are right angle and its shape resembles that of an egg. It can also be called as duodecagon . A regular dodecagon has all the sides equal, and all its interior angles measure 116o .

**Hendecagon **

It is an 11 sided plane figure in which all the angles are right size and its shape resembles that of an egg.

**Diamond**

A diamond shape is a quadrilateral with both pairs of opposite sides passing through same two points.

**Trapezoid **

It is a four sided plane figure which has one pair of parallel sides and the other sides are not parallel to each other.

**Kite **

It is an obtuse angled parallelogram in which one set of opposite sides are equal in length and other set of opposite sides are equal but right angled. In other words, it can be said as a quadrilateral with two sets of adjacent congruent sides (non-parallel).

**Rhombus Square **

It is a rhombus with equal diagonals. It looks like a square form where all the four angles have been divided into two equal parts. The ratio of a side of a rhombus square to its diagonals is the same as that of a square.

**Parallelogram Square **

It is a parallelogram with equal diagonals. It looks like an elongated form of a square where all the four angles have been divided into two equal parts and the base line has also been extended horizontally.

**Trapezoid Diamond **

A trapezoid diamond shape is formed by joining midpoints of opposite sides of an obtuse angled quadrilateral. Its lower base angles are acute, its upper base angles are obtuse and there is always one pair of parallel lines.

**Line segment**

A line segment is a part of a straight line. It has two end points.

**Parallel lines **

In geometry, parallel lines are a pair of lines in a plane which do not intersect each other and have the same direction throughout their entire length. The distance between these parallel lines is always same.

**Perpendicular lines **

In geometry, perpendicular lines are a pair of lines which intersect at a right angle i.e., 90o . In other words, they form four right angles together by joining their points or vertices where they cross on each other. The ratio of length of line segments to the perpendicular bisector on which it lies is called as slant height . Both acute and obtuse triangles can be formed using lines parallel and perpendicular to each other.

**Right Triangle**

In aa right triangle , the side of length called as hypotenuse is opposite to angle of 90o . In other words, it is the side which is across from the right angle. The longest side that lies opposite to 90o is always called as hypotenuse.In a right triangle, the sides must be in proportion i.e., if one leg has a particular length then other leg also has this same length and similarly for the hypotenuse.

**Acute Triangle**

An acute triangle is a triangle with 3 acute angles or angles measuring less than 90o. It can also be said that all three angles in an acute triangle are less than 90o .

**Obtuse Triangle **

An obtuse triangle is a triangle with one obtuse angle or an angle greater than 90o . In other words, all three angles in an obtuse triangle are more than 90o

**Isosceles Triangle **

An isosceles triangle has two equal sides and the unequal side is across from the vertex of the right size. The angles opposite to equal sides are always same i.e., they have got same measure. An isosceles triangle has at least one pair of parallel lines because there are two pairs of equal sides present.

**Scalene Triangle **

A scalene triangle does not have any equal sides; hence it has no equal angles either. All its sides are different lengths and all its interior angles too are different sizes.