Download Math Vocabulary Words

Math Vocabulary Words
Third Grade
by
Serena Georges
2-dimensional
figure
Plane figures that have
length and width
3-dimensional
figure
3-dimensional figures
with edges, faces
and/or corners
addend
2 + 3 = 5;
The addends are 2 and 3.
A number that is added
to another in an
addition problem
addition
3+2=5
The process of finding the
total number of items when
two or more groups of items
are joined
analog
clock
A clock with numbers 1 through
12 around the face with rotating
hands to show hours, minutes
and seconds
area
area =
9 square units
The number of square
units needed to cover a
surface
array
3 x 4 = 12
An arrangement that
shows objects in rows
and columns
attribute
Characteristics, size,
shape and/or color
bar graph
A graph that uses bars
to show data
capacity
The amount a
container can hold
when filled
centimeter
100 centimeters =
1 meter
A metric unit for
measuring length
circle
A closed 2D shape that
is perfectly round
closed
figure
A figure that begins
and ends at the same
point
cone
A solid 3-d pointed
figure that has a flat,
round base with an
apex
congruent
figures
Figures that have the
same size and shape
corner
vertex
vertices
The place where two or
more edges meet
cube
A solid figure with six
congruent square faces
and twelve vertices
(corners)
cubic
units
The volume
of this figure
is 24 cubic
units
3 x 2 x 4 = 24
A standard unit for
measuring volume
Example:
cup
2 cups = 1 pint
A customary unit used
to measure capacity
cylinder
A solid 3-d figure that is
shaped like a can
Examples:
decimal
0.5 five tenths
0.25 twenty-five
hundredths
A number with one or
more digits to the right
of the decimal point
decimal
point
A symbol used to separate
dollars from cents in money
and to separate the ones
place from the tenths place
in decimals
degree
A unit for measuring
temperature
degree
Celsius
(°C)
A metric unit for
measuring temperature
degree
Fahrenheit
(°F)
A customary unit for
measuring temperature
denominator
The number below the bar
in a fraction. It tells the total
number of equal parts or
groups into which the whole
Example:
difference
8-3=5
5 is the difference
The answer in a
subtraction problem
digit
0, 1, 2, 3, 4, 5,
6, 7, 8, 9
Any one of the ten
symbols 0, 1, 2, 3, 4, 5,
6, 7, 8, or 9 used to
write numbers
digital
clock
A clock that uses
numerals only to tell
the time
divide
6 divided by 3 = 2
To separate into equal
groups
35 ÷ 5 = 7
dividend
The dividend is 35.
The number that is to
be divided
18 ÷ 3 = 6
divisor
The divisor is 3.
The number that
divides the dividend
elapsed
time
From 3:00 p.m. to 4:00 p.m. the
elapsed time is one hour.
The amount of time that
passes from the start of
an activity to the end of
that activity
edge
The line segment
where two faces of a
solid figure meet
equal
to
45
45
Sign used to show
numbers with the same
value
equally
likely
It is equally likely to pull a circle
and a square because they have
equal amounts
Outcomes that have
the same chance of
happening
equivalent
fractions
Two or more fractions
that name the same
amount
estimate
Example:
23
20
36
+40
About
60
To use rounding to find
out about how many
even
number
0, 2, 4, 6, 8,
10, 12, 14, 16,
18, 20. . .
A whole number that
has 0, 2, 4, 6, or 8 in
the ones place
241 =
expanded
200 + 40 + 1
form
A way to write numbers
by showing the value
of each digit
face
A flat surface of a 3-d
figure
fact
family
Examples:
2+4=6
6-4=2
4+2=6
6-2=4
or
3 X 6 = 18
18 ÷ 6 = 3
6 X 3 = 18
18 ÷ 3 = 6
Related facts using the
same numbers
factors
3 x 8 = 24
The factors are 3
and 8
The numbers that are
multiplied to give a
product
fraction
A number that names
part of a whole (region)
or part of a group
foot
(ft)
A customary unit used
to measure length.
1 foot = 12 inches
gallon
A customary unit used
to measure capacity
4 quarts = 1 gallon
gram
(g)
A paper clip has a mass of
about 1 gram.
A metric unit used to
measure mass
greater
than
64
56
Sign used to compare
numbers
hexagon
A polygon with 6 sides
and 6 angles
heptagon
A polygon with 7 straight
sides and 7 angles
inch
A customary unit used
to measure length
12 inches = 1 foot
kilogram
(kg)
A metric unit used to
measure mass
1,000 grams (g) – 1 kilogram (kg)
kilometer
(km)
A unit used to measure
distance
1 km – 1,000 meters (m)
length
The distance of an
object measured from
one end to the other
least
likely
It is least likely to pull
a triangle
An event that has a
lesser chance of
happening
less
than
56
64
Sign used to compare
numbers
line
segment
Part of a line with two
endpoints
line
symmetry
A line that divided a
figure into two
congruent parts
liter
(L)
A metric unit that is
used to measure
capacity
meter
(m)
A metric unit used to
measure length or
distance
measurement
The act of measuring
to determine the size of
something
mile
(mi)
A customary unit used
to measure length or
distance
milliliter
(ml)
A small spoon holds about
5 milliliters.
A metric unit used to
measure capacity
1,000 milliliter (ml) = 1 liter (L)
millimeter
(mm)
A unit of length
10 millimeter (mm) = 1 centimeter (cm)
minutes
Minutes measure short
amount of time. There
are 60 minutes in one
hour.
minute
hand
The long hand on a
clock
most
likely
It is most likely to pull a
square because there are
more squares than circles
An event that has a
greater chance of
happening
multiplication
3 x 4 = 12
An operation using
repeated addition with
two or more numbers
number
line
A line with equally
spaced ticks and
numbers
numeral
45
23
67
18
98
A symbol that stands
for a number
numerator
The number above the
fraction bar in a fraction.
Tells how many equal
parts.
open
figure
A figure that does not
begin and end at the
same point
ordered
pair
A pair of numbers used to locate a
point on a grid. The first number
tells the left-right position and the
second number tells the up-down
position
octagon
A polygon with 8 sides
and 8 angles
odd
number
Example:
1, 3, 5, 7, 9,
11, 13, 15,
17, 19,… . .
A whole number that
has 1, 3, 5, 7 or 9 in
the ones place
ounce
An ounce of gold
A customer unit used
to measure weight
ordinal
number
A number telling order
or position
parallel
lines
Example:
Lines that never cross
and are always the
same distance apart
parallelogram
A plane figure with 2 pairs of
parallel sides, 2 pairs of equal
angles and 2 pairs of equal
sides
pattern
Repeated design or
number sequence
pentagon
A polygon with 5 sides
and 5 angles
perimeter
2 cm + 3 cm + 3 cm = 8 cm
The perimeter of this
figure is 8 cm.
The distance around a
figure
pictograph
A graph that uses
pictures to show and
compare information
pint
A customary unit used to
measure capacity
2 cups = 1 pint
place
value
Hundreds Tens Ones
4
5
0
The value of the 5 is 50
or 5 tens.
The value of a digit
depending on its place
in number
plane
figure
A figure in a plane that
is formed by lines that
are curved, straight or
both
polygon
A closed plane figure
with straight sides
pound
A customary unit used
to measure weight
point

A position on a number
line or in space
product
6 X 2 = 12
The product is 12
The answer to a
multiplication problem
quadrilateral
A polygon with 4
angles and 4 sides
quart
A customary unit used
to measure capacity
2 pints = 1 quart
quotient
35 ÷ 5 = 7
The quotient is 7
The answer in a
division problem
rectangle
A plane figure with 4
sides and 4 right
angles
rectangular
prism
A solid 3-d figure in
which all 6 faces are
rectangles
reflection
(flip)
A move that involves
flipping a figure over a
line
Example:
regroup
23 = 2 tens 3 ones
or 1 ten 13 ones
To exchange amounts
of equal value to
rename a number
remainder
The number that is left
over after dividing
rhombus
A 2D figure with four
equal sides whose
opposite sides are parallel
right
angle
A right angle is a special
angle. The corners of a
sheet of paper are at right
angles.
round
Example:
23
20
36
40
When you round a
number to the nearest
ten, you find the ten
that’s closest
rotation
(turn)
A move that involves
turning a figure
solid
figure
3-dimensional figures
with edges, faces
and/or corners
sphere
Any round object whose
curved surface is the same
distance from the center to
all its points
square
A plane figure with 4
equal sides and 4 right
angles
square
pyramid
A solid 3-d figure with a
base that is a square and
four faces that are triangles
with a common point
standard
form
Example:
2,394
A way to write number by
using the digits 0-9, with
each digit having a place
value
subtraction
6-2=4
An operation on two or
more numbers to find
the difference
sum
Example:
12 + 7 = 19
The sum is 19
The answer to an
addition problem
symmetry
When one half of a figure
looks like the mirror
image of the other half
tally
table
A way to organize data
using tally marks to show
how often something
happens
temperature
A measurement of how
hot or cold something
is
tenth
One of ten equal parts
thermometer
An instrument for
measuring temperature
translation
(slide)
A move that slides a figure
a given distance in a given
direction
triangle
A plane figure with 3
sides and 3 angles
triangular
prism
A 3-d figure (solid) with
two identical, triangular
bases
triangular
pyramid
A 3-d figure (solid) with a
triangular base and
triangular faces that come
to a point
volume
The volume
of this figure
is 24 cubic
units
3 x 2 x 4 = 24
The measure of space
a solid figure occupies
width
The measurement of
an object from side to
side
whole
{0, 1, 2, 3, . . .}
numbers
The set of numbers
that includes 0 and all
natural numbers
word form
two-hundred
fifty-seven
A way to write numbers
by using words
yard
(yd)
A customary unit used
to measure length
1 yard = 3 feet