Grade 4Glossary
 acute angle
 Unit 7 Lesson 12
An angle that measures less than 90 degrees.
 angle
 Unit 7 Lesson 5
A figure made up of two rays that share the same endpoint.
 common denominator
 Unit 2 Lesson 15
The same denominator in two or more fractions. For instance,
and have a common denominator.  composite number
 Unit 1 Lesson 3
A whole number with more than 1 factor pair.
 denominator
 Unit 2 Lesson 1
The bottom part of a fraction that tells how many equal parts the whole was partitioned into.
 dividend
 Unit 6 Lesson 13, Unit 6 Lesson 20
The number being divided. For example, when 37 is divided by 5, we call 37 the dividend.
 equivalent fractions
 Unit 2 Lesson 4
Fractions that have the same size and describe the same point on the number line. For example,
and are equivalent fractions.  expanded form
 Unit 4 Lesson 8, Unit 4 Lesson 11
A specific way of writing a number as a sum of hundreds, tens, and ones.
Expanded form writes a number as a sum of the value of each digit. Example: 482 written in expanded form is
.  factor pair of a whole number
 Unit 1 Lesson 2
A pair of whole numbers that multiply to result in that number. For example, 5 and 4 are a factor pair of 20.
 intersecting lines
 Unit 7 Lesson 3, Unit 7 Lesson 5
Lines that cross.
 line
 Unit 7 Lesson 2

A set of points that are arranged in a straight way and extend infinitely in opposite directions.
 line of symmetry
 Unit 8 Lesson 4
A line that divides a figure into two halves that match up exactly when the figure is folded along the line.
 mixed number
 Unit 3 Lesson 8, Unit 3 Lesson 14
A number expressed as a whole number and a fraction less than 1.
 multiple of a number
 Unit 1 Lesson 1
The result of multiplying that number by a whole number. For example, 18 is a multiple of 3, because it is a result of multiplying 3 by 6.
 numerator
 Unit 2 Lesson 1

The top part of a fraction that tells how many of the equal parts are being described.
 obtuse angle
 Unit 7 Lesson 12
An angle that measures greater than 90 degrees.
 parallel lines
 Unit 7 Lesson 3, Unit 7 Lesson 5
Lines that never intersect.
 perpendicular lines
 Unit 7 Lesson 10
Lines that intersect creating right angles.
 point
 Unit 7 Lesson 1

A location along a line or in space.
 prime number
 Unit 1 Lesson 3
A whole number that is greater than 1 and has exactly one factor pair: the number itself and 1.
 ray
 Unit 7 Lesson 2
A line that ends at one point and goes on in the other direction.
 remainder
 Unit 6 Lesson 20
The number left over when we take away as many equal groups as we can from a number.
 right angle
 Unit 7 Lesson 8
An angle with a measurement of 90 degrees.
 rounding
 Unit 4 Lesson 16

A formal way to say which number a given number is closer to. For example, for 182, the number 180 is the closest multiple of ten and 200 is the closest multiple of a hundred. We can round 182 to 180 (if rounding to the nearest ten) or 200 (if rounding to the nearest hundred).
 segment or line segment
 Unit 7 Lesson 1

A part of a line with two endpoints.
 straight angle
 Unit 7 Lesson 12
An angle that measures 180 degrees.
 symmetry
 Unit 8 Lesson 4, Unit 8 Lesson 6
A figure has symmetry if its parts can match up exactly when the figure is folded or rotated.
 vertex
 Unit 7 Lesson 5
The point where the two rays meet.