Geometry
Geometry is the study of shapes, sizes, positions, and properties of space. It covers everything from basic angle relationships and triangle properties to circles, area, volume, and coordinate geometry. Whether you are working on proofs, calculating surface area, or exploring transformations, this page links to every geometry term on Mathwords.
Key Concepts
Area of a kite is half the product of its two diagonals. Because the diagonals of a kite are always perpendicular to ...
A kite is a quadrilateral that has two pairs of adjacent sides that are congruent. Its diagonals are perpendicular to...
The Euler line is the straight line that passes through a triangle's orthocenter, centroid, and circumcenter. For any...
Inverse sine is the function that takes a ratio (between −1 and 1) and returns the angle whose sine equals that ratio...
Inverse sine is the function that takes a ratio (between −1 and 1) and returns the angle whose sine equals that ratio...
Inverse sine is the function that takes a ratio (between −1 and 1) and returns the angle whose sine equals that ratio...
Inverse sine is the function that takes a ratio (between −1 and 1) and returns the angle whose sine equals that ratio...
Inverse sine is the function that takes a ratio (between −1 and 1) and returns the angle whose sine equals that ratio...
Equation of a line is an algebraic equation whose solutions form a straight line when plotted on a coordinate plane. ...
Volume is the total amount of three-dimensional space enclosed within a solid figure. It is measured in cubic units, ...
Surface area is the total area of all the outer faces and curved surfaces of a three-dimensional solid. It is measure...
The graph of an equation or inequality is the visual picture formed by plotting every point whose coordinates satisfy...
All Geometry Terms (348)
- AA Similarity
- AAS Congruence
- Abscissa
- Accuracy
- Acute Angle
- Acute Triangle
- Adjacent
- Adjacent Angles
- Alternate Angles
- Alternate Exterior Angles
- Alternate Interior Angles
- Altitude
- Altitude of a Cone
- Altitude of a Cylinder
- Altitude of a Parallelogram
- Altitude of a Prism
- Altitude of a Pyramid
- Altitude of a Trapezoid
- Altitude of a Triangle
- Analytic Geometry
- Angle
- Angle Bisector
- Angle of Depression
- Angle of Elevation
- Angle Sum Property of a Triangle
- Annulus
- Antipodal Points
- Apex
- Apothem
- Arc of a Circle
- arccos
- arcsin
- arctan
- Area of a Circle
- Area of a Convex Polygon
- Area of a Kite
- Area of a Parallelogram
- Area of a Rectangle
- Area of a Regular Polygon
- Area of a Rhombus
- Area of a Sector of a Circle
- Area of a Segment of a Circle
- Area of a Trapezoid
- Area of a Triangle
- Area of an Equilateral Triangle
- Arm of a Right Triangle
- Arm of an Angle
- ASA Congruence
- Axes
- Axis of a Cylinder
- Axis of Reflection
- Axis of Rotation
- Axis of Symmetry
- Base (Geometry)
- Base of a Trapezoid
- Base of a Triangle
- Base of an Isosceles Triangle
- Between
- Bisect
- Bisector
- Box
- Cartesian Coordinates
- Cartesian Form
- Cartesian Plane
- Cavalieri’s Principle
- Center of Rotation
- Centers of a Triangle
- Central Angle
- Centroid
- Centroid Formula
- Ceva’s Theorem
- Cevian
- Chord
- Circle
- Circular Cone
- Circular Cylinder
- Circular Functions
- Circumcenter
- Circumcircle
- Circumference
- Circumscribable
- Circumscribed
- Coincident
- Collinear
- Complement of an Angle
- Complementary Angles
- Composite
- Compression
- Compression of a Geometric Figure
- Compute
- Concave
- Concentric
- Concurrent
- Cone
- Cone Angle
- Congruence Tests for Triangles
- Congruent
- Consecutive Interior Angles
- Contrapositive
- Convex
- Coordinates
- Coplanar
- Corresponding
- cos
- CPCFC
- CPCTC
- Cube
- Cube Root
- Cylinder
- Decagon
- Degenerate
- Degree (angle measure)
- Diagonal of a Polygon
- Diameter
- Diametrically Opposed
- Dihedral Angle
- Dilation
- Dilation of a Geometric Figure
- Dimensions
- Direct Proportion
- Disk
- Distance Formula
- Distinct
- Dodecagon
- Dodecahedron
- Double Cone
- Edge of a Polyhedron
- Elliptic Geometry
- Equation of a Line
- Equiangular Triangle
- Equidistant
- Equilateral Triangle
- Euclidean Geometry
- Euler Line
- Euler's Formula (Polyhedra)
- Evaluate
- Exact Values of Trig Functions
- Exterior Angle of a Polygon
- Exterior Angle Theorem
- Face of a Polyhedron
- Fibonacci Sequence
- Fixed
- Flip
- Formula
- Fractal
- Frustum of a Cone or Pyramid
- Geometric Figure
- Geometric Mean
- Geometric Solid
- Geometry
- Glide
- Glide Reflection
- Golden Mean
- Golden Rectangle
- Golden Spiral
- Graph of an Equation or Inequality
- Great Circle
- Heptagon
- Hero’s Formula
- Hexagon
- Hexahedron
- HL Congruence
- HL Similarity
- Horizontal
- Hyperbolic Geometry
- Hypotenuse
- Icosahedron
- Image of a Transformation
- Incenter
- Incircle
- Inradius
- Inscribed Angle in a Circle
- Interior
- Interior Angle
- Invariant
- Isometry
- Isosceles Trapezoid
- Isosceles Triangle
- Kite
- Lateral Area
- Lateral Surface/Face
- Law of Cosines
- Law of Sines
- Leg of a Trapezoid
- Leg of an Isosceles Triangle
- Line
- Line Segment
- Linear
- Linear Pair of Angles
- Locus
- Magnitude
- Major Arc
- Mean
- Measure of an Angle
- Measurement
- Median of a Trapezoid
- Median of a Triangle
- Mensuration
- Midpoint
- Midpoint Formula
- Midsegment
- Minor Arc
- Minute
- Möbius Strip
- n-gon
- Negative Reciprocal
- No Slope
- Non-Adjacent
- Non-Euclidean Geometry
- Nonagon
- Noncollinear
- Number Line
- Oblique
- Oblique Cone
- Oblique Cylinder
- Oblique Prism
- Oblique Pyramid
- Obtuse Angle
- Obtuse Triangle
- Octagon
- Octahedron
- Octants
- One Dimension
- Ordinate
- Origin
- Orthocenter
- Oval
- Parallel Lines
- Parallel Planes
- Parallel Postulate
- Parallelepiped
- Parallelogram
- Pentagon
- Perimeter
- Perpendicular
- Perpendicular Bisector
- Phi (Φ φ)
- Pi (Π π)
- Plane
- Plane Figure
- Plane Geometry
- Platonic Solids
- Point
- Point of Symmetry
- Polygon
- Polygon Interior
- Polyhedron
- Pre-Image of a Transformation
- Precision
- Prism
- Proportional
- Pyramid
- Pythagorean Identities
- Pythagorean Theorem
- Pythagorean Triple
- Quadrangle
- Quadrants
- Radian
- Radical
- Radicand
- Radius of a Circle or Sphere
- Ray
- Rectangle
- Regular Polygon
- Regular Prism
- Regular Pyramid
- Regular Right Prism
- Regular Right Pyramid
- Regular Tetrahedron
- Rhombus
- Right Angle
- Right Circular Cone
- Right Circular Cylinder
- Right Cone
- Right Cylinder
- Right Prism
- Right Pyramid
- Right Square Prism
- Right Triangle
- Root of a Number
- Rotation
- SAS Congruence
- SAS Similarity
- Scale Factor
- Scalene Triangle
- Secant Line
- Second
- Sector of a Circle
- Segment of a Circle
- Self-Similarity
- Semicircle
- Semiperimeter
- Side of a Polygon
- Similar
- Similarity Tests for Triangles
- sin
- Skew Lines
- Slant Height
- Slope of a Line
- SOHCAHTOA
- Solid Geometry
- Sphere
- Square
- Square Root
- SSA
- SSS Congruence
- SSS Similarity
- Standard Position
- Stewart's Theorem
- Straight Angle
- Supplement
- Supplementary Angles
- Surd
- Surface
- Surface Area
- Symmetric
- Takeout Angle
- tan
- Tangent Line
- Tessellate
- Three Dimensional Coordinates
- Three Dimensions
- Torus
- Transformations
- Transversal
- Trapezium
- Trapezoid
- Triangle
- Triangle Inequality
- Trig
- Truncated Cone or Pyramid
- Truncated Cylinder or Prism
- Two Dimensions
- Undecagon
- Unit Circle
- Varignon Parallelogram of a Quadrilateral
- Vertex
- Vertical
- Vertical Angles
- Volume
- x-intercept
- x-y Plane
- x-z Plane
- y-intercept
- y-z Plane
- z-intercept
- Zero Dimensions
- Zero Slope