Geometry
Geometry has 31 English words, such as acute angle, acute triangle, base, and circle. Learn them with pictures, IPA, meanings and example sentences.
What you'll gain
All 31 words in Geometry
acute angle
An acute angle is an angle that measures more than 0° and less than 90°.
A 35° angle is an acute angle.
acute triangle
A triangle whose three interior angles are each less than 90 degrees.
An acute triangle has three angles that are each less than 90 degrees.
base/beɪs/v
n. in geometry, the bottom side or face of a shape, on which it stands; n. the lowest part of something, on which it rests.
circle/ˈsɜːrkl/n
n. a perfectly round flat shape, every point of which is the same distance from the centre; v. to draw a ring around something.
cone/koʊn/
A cone is a solid or hollow object that tapers from a round base to a point.
cube/kjub/
A cube is a solid object with six equal square sides.
cylinder/ˈsɪləndɚ/
A solid or hollow geometric shape with straight parallel sides and circular or oval ends.
diagonal/daɪ̯ˈeɪ̯ɡ(ə)nəl/
adj. slanting, oblique; n. line segment, cross line
diameter/daɪˈæmɪdɚ/
n. a straight line drawn from one side of a circle to the other through the centre, and the length of that line.
ellipse/ɪˈlɪps/
An ellipse is a regular oval shape, like a circle that has been stretched in one direction.
heptagon
A polygon with seven sides and seven angles.
The school project shows a blue heptagon with seven equal sides.
hexagon/ˈhɛksəɡɑn/
A hexagon is a flat geometric shape that has six straight sides and six angles.
hypotenuse/haɪˈpɑtənus/
The hypotenuse is the longest side of a right-angled triangle, positioned opposite the right angle.
isosceles triangle
A triangle with at least two sides of equal length; the angles opposite those sides are also equal.
An isosceles triangle has two equal sides and two equal base angles.
length/leŋθ/n
Length is the measurement of how long something is from one end to the other.
obtuse angle
An angle that measures more than 90 degrees but less than 180 degrees.
The roof's wide corner forms an obtuse angle.
octagon/ˈɑktəˌɡɑn/
An octagon is a geometric flat shape that has eight sides and eight angles.
oval/ˈoʊvəl/
An oval is a shape that is curved and shaped like a flat egg.
pentagon/ˈpɛntəˌɡɑn/
A flat geometric shape that has five straight sides and five angles.
pyramid/ˈpɪɹəməd/
n. tomb, structure; n. polyhedron, solid shape
radius/ɹˈeɪdɪəs/n
The radius is a straight line extending from the center of a circle to its circumference, or one of the two bones in the human forearm.
rectangle/ˈrɛktæŋɡl̩/n
n. a flat shape with four straight sides and four right angles, where the opposite sides are equal in length.
right angle
An angle that measures exactly 90 degrees, formed by two perpendicular lines.
The corner of the square forms a right angle.
right triangle
A triangle with one angle measuring exactly 90 degrees.
In geometry class, we used the Pythagorean theorem to find the longest side of a right triangle.
scalene triangle
A triangle whose three sides have different lengths.
In geometry class, we measured each side of the scalene triangle and found a different length.
side/saɪd/n
n. one of the straight lines that form the edge of a flat shape; n. one of the surfaces or edges of an object.
sphere/sfɪr/n
n. a perfectly round solid shape, like a ball; n. an area of activity or interest.
square/skwer/n
n. a flat shape with four equal straight sides and four right angles; n. an open public space in a town; v. to multiply a number by itself.
trapezoid/ˈtɹæpəzɔɪd/
A trapezoid is a four-sided geometric shape with at least one pair of parallel sides.
triangle/ˈtraɪæŋɡl/noun
n. a small percussion instrument made of a steel rod bent into a triangle and struck with a metal beater; n. a flat shape with three straight sides and three angles.
width/ˈwɪtθ/n
n. the distance from one side of something to the other.