Geometry Vocabulary
* Students should know the meaning of these geometry terms and also
be able to draw or identify pictures of these terms.
* Students will be tested on all of these terms.
Lines and Angles
vertex  point at which two rays meet to form an angle
perpendicular  lines that meet at a right angle
parallel  lines that are the same distance apart (will never cross)
midpoint  the halfway point on a line segment
line segment  a section of a line, has an endpoint on each end
line  a line that never ends, continues on in both directions
ray  a line beginning from a point
acute angle  an angle that measures less than 90 degrees
right angle  an angle that measures exactly at 90 degrees
obtuse  an angle that measures greater than 90 degrees
straight angle  an angle that measures 180 degrees
Polygons
regular polygon  two dimensional shape with equal sides and angles
irregular polygon  two dimensional shape with different lengths and angles
quadrilateral  any four sided polygon
square  a quadrilateral with 4 equal sides and 4 right angles
rectangle  opposite sides are equal and all 4 angles are right angles
parallelogram  2 pairs of parallel lines
rhombus  a shape with 4 equal sides but no right angles
trapezoid  a shape with 4 sides but only 1 set of parallel lines
pentagon  a five sided polygon
hexagon  a six sided polygon
heptagon  a seven sided polygon
octagon  an eight sided polygon
Circles and Triangles
circumference  the distance around a circle
radius  the distance from the center of a circle to the edge of a circle
diameter  the distance across the circle, passing through the center
chord  a line segment connecting one point on a circle to another point
equilateral  a triangle with all sides and angles equal
scalene  a triangle which no sides are the same length
isosceles  a triangle which has two sides the same length

The following websites provide additional reinforcement of our geometry skills.
http://www.math.com/practice/Geometry.html
http://www.aplusmath.com/cgibin/games/geomatho
http://www.bbc.co.uk/schools/ks2bitesize/maths/shape_space/shapes/play.shtml
http://www.aplusmath.com/cgibin/Flashcards/geoflash
http://www.proprofs.com/quizschool/story.php?title=4thgradeGeometry
http://www.tlsbooks.com/fourthgradeworksheets.htm
http://quizlet.com/76576/4thgradegeometrytermsflashcards/
