Geometry - Introductory

If you feel obtuse when it comes to angles, review this list of geometry terms. You'll learn about planes, polygons, perimeter, and more. It's as easy as pi!
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Full list of words from this list:

words only definitions & notes
  1. acute
    (of an angle) less than 90 degrees
  2. angle
    the space between two lines or planes that intersect
  3. arc
    a continuous portion of a circle
  4. area
    the extent of a two-dimensional surface within a boundary
  5. attribute
    a characteristic that distinguishes objects or individuals
  6. axis
    a straight line through a body or figure
  7. base
    the bottom side of a geometric figure
  8. category
    a collection of things sharing a common attribute
  9. center
    a point equidistant from the ends of a line
  10. circle
    a plane curve with every point equidistant from the center
  11. circular
    having a circular shape
  12. cone
    a shape with a circular base and sides tapering to a point
  13. coordinate
    a number that identifies a position relative to an axis
  14. coordinate system
    a system that uses coordinates to establish position
  15. cube
    a three-dimensional figure with six equal squares as faces
  16. cubic
    having three dimensions
  17. cylinder
    a solid bounded by a round surface and two parallel planes
  18. degree
    a measure for arcs and angles
  19. dimension
    the magnitude of something in a particular direction
  20. edge
    a line determining the limits of an area
  21. equal
    having the same quantity, value, or measure as another
  22. equilateral triangle
    a three-sided regular polygon
  23. face
    a surface forming part of the outside of an object
  24. feature
    a prominent attribute or aspect of something
  25. figure
    alternate name for the body of a human being
  26. formula
    a group of symbols that make a mathematical statement
  27. graph
    a visual representation of the relations between quantities
  28. height
    distance from the base of something to its top
  29. hexagon
    a six-sided polygon
  30. hierarchy
    a series of ordered groupings within a system
  31. horizontal
    parallel to or in the plane of the horizon or a base line
  32. intersect
    meet or cross at a point; overlap
  33. intersection
    the act of meeting at a point
  34. isosceles
    (of a triangle) having two sides of equal length
  35. isosceles triangle
    a triangle with two equal sides
  36. length
    the linear extent in space from one end to the other
  37. line
    a length between two points
  38. measure
    determine the dimensions of something or somebody
  39. measurement
    assigning numbers to phenomena according to a rule
  40. obtuse
    of an angle, between 90 and 180 degrees
  41. octagon
    a shape with eight angles and eight sides
  42. origin
    the point of intersection of axes on a coordinate plane
  43. overlap
    extend over and cover a part of
  44. parallel
    being everywhere equidistant and not intersecting
  45. parallelogram
    a quadrilateral whose opposite sides are parallel and equal
  46. partition
    divide into parts, pieces, or sections
  47. pentagon
    a shape with five angles and five sides
  48. perimeter
    a line enclosing a plane area
  49. perpendicular
    intersecting at or forming right angles
  50. plane
    an unbounded two-dimensional shape
  51. plane figure
    a two-dimensional shape
  52. point
    a geometric element that has position but no extension
  53. polygon
    a closed plane figure bounded by straight sides
  54. prism
    a polyhedron with two congruent and parallel faces
  55. property
    a basic or essential attribute shared by members of a class
  56. protractor
    drafting instrument used to draw or measure angles
  57. quadrant
    any of the four areas into which a plane is divided
  58. quadrilateral
    a four-sided polygon
  59. ray
    (mathematics) a straight line extending from a point
  60. rectangle
    a parallelogram with four right angles
  61. rectangular
    having four right angles
  62. rectilinear
    characterized by a straight line or lines
  63. rhombus
    a parallelogram with four equal sides
  64. right angle
    the 90 degree angle between two perpendicular lines
  65. right triangle
    a triangle with one right angle
  66. scalene
    having three sides of different lengths
  67. scalene triangle
    a triangle with no two sides of equal length
  68. shape
    a perceptual structure
  69. side
    a line segment forming part of the perimeter of a plane figure
  70. solid figure
    a three-dimensional shape
  71. sphere
    a solid figure bounded by a round surface
  72. square
    a polygon with four equal sides and four right angles
  73. symmetric
    having similarity in size, shape, and relative position of corresponding parts
  74. symmetrical
    having similarity in corresponding parts
  75. symmetry
    exact reflection of form on opposite sides of a line
  76. tiling
    the application of tiles to cover a surface
  77. trapezoid
    a quadrilateral with one pair of parallel sides
  78. triangle
    a three-sided polygon
  79. two-dimensional
    involving measurements of magnitude in two directions
  80. unit
    a division accepted as a standard of measurement or exchange
  81. value
    a numerical quantity measured or assigned or computed
  82. vertex
    the point of intersection of lines
  83. vertical
    at right angles to the plane of the horizon or a base line
  84. volume
    the amount of 3-dimensional space occupied by an object
  85. whole
    all of something, including all of its elements or parts
  86. width
    the extent of something from side to side
  87. x-axis
    the horizontal axis in a plane coordinate system
  88. y-axis
    the vertical axis in a plane coordinate system
Created on Thu Feb 09 13:49:18 EST 2017 (updated Wed Mar 29 15:53:16 EDT 2017)

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