Second Grade Math Vocabulary
A
a.m. A time between12:00 midnight and 12:00 noon
add To combine;put together two or more quantities
addend 5+ 3+ 2= 10Any number being added
Additive Identity Property of Zero Adding zero to a number gives a sum identical to the given number
analog clock A clock that shows the time by the positions of the hour and minute hand
angle The shape formed when two sides meet at the vertex.
array An arrangement of objects in equal rows and equal columns.
Associative Property of Addition Changing the grouping of three or more addends does not change the sum
attribute A characteristic of an object, such as color, shape, size, etc
B
bar graph A graph that uses height or length of rectangles to compare data
bar model A model that uses bars to represent known and unknown quantities and the relationship between these quantities
base-ten numeral form A common way of writing a number using digits. The value of a numeral depends on where it appears in the number. (also known as standard form)
base-ten numerals Any of the symbols 0, 1, 2, 3, 4, 5, 6, 7, 8, or 9. (also known as digits)
C
category A collection of things sharing a common attribute
cent A unit of money. A penny is one cent or 1¢. 100 cents = one dollar
centimeter (cm) A metric unit of length. 100 centimeters = 1 meter
circle A closed shape with no sides and no vertices
closed shape A shape with all the sides connected
column A vertical arrangement of numbers or information in an array or table
Commutative Property of Addition Changing the order of the addends does not change the sum
compare To decide if one number is greater than, less than, or equal to another
compensation A strategy that involves adjusting one addend to a tens number, and then adjusting the other addend to keep the balance.
compose To put together smaller numbers to make larger numbers
cone A solid shape with a circular base, a curved surface, and one vertex
count back A way to subtract
count on A way to add
count up A way to subtract. Finding the difference by adding up from the smaller number to the larger number
cube A solid shape with 6square faces
customary system A system of measurement used in the United States
cylinder A solid shape with 2 circular bases and a curved surface
D
data A collection of information
decimal point $1.55 decimal point A dot (.) used to separate dollars from cents in money amounts
decompose To separate a number into 2 or more part 349= 300+40+9
difference 3 –2 = 1The result when one number is subtracted from another
digit Any of the symbols 0, 1, 2, 3, 4, 5, 6, 7, 8, or 9. (also known as base-ten numerals)
digital clock A clock that shows the time with numbers of hours and minutes, usually separated with a colon. (:)
dime10 ¢A coin worth 10 cents
dollar100 cents or $1.00An amount of money equal to 100 cents
doubles 4 + 4 = 8 In a double, both addends are the same.Addition facts with two addends that are the same
E
edge The place where two flat surfaces of a solid shape meet
equal Having the same amount, size, number, or value
equal groups 3 equal groups of 5Groups that have the same number of objects
equal parts 3 equal parts Parts of an object or group that have been divided equally into pieces. (also known as equal shares)
equal shares 3 equal shares Parts of an object or group that have been divided equally into pieces. (also known as equal parts)
equation A number sentence with an equal sign. The amount on one side of the equal sign has the same value as the amount on the other side
estimate A number close to an exact amount. An estimate tells about how much or about how many
even number 8 is even.An even number can be shown as 2 equal parts. An even number has 0, 2, 4, 6, or 8 in the ones place
expanded form A way to write numbers that shows the place value for each digit 3Hundreds+2Tens+3ones=300+20+3 =323
expression A mathematical phrase without an equal sign 24+6
F
face A flat surface on a solid shape
fact family A group of related facts that use the same numbers. (also known as related facts)
fewer Smaller quantity or amount
foot (ft) A customary unit of length equal to 12 inches. (plural -feet)
fourth of One of 4 equal parts
fourths The parts you get when you divide something into4 equal parts
G
greater than Greater than is used to compare two numbers when the first number is larger than the second number6>2
H
half hour30 minutes = one half-hour A unit of time equal to30 minutes
half of One of 2 equal parts
half past 30 minutes after the hour
halves The parts you get when you divide something into 2 equal parts
hexagon A shape with 6 straight sides
horizontal bar graph A graph that uses length of rectangles to compare data
hour (hr) 60 minutes = 1 hour A unit of time equal to60 minutes
hour hand A short hand on a clock
hundred A number equal to 10 tens or 100 ones
hundreds HundredsTensOnes243The value of a digit that is the third position from the right when describing whole number place value
I
inch (in) A customary unit of length. 12 inches = 1 foot
J
K
key A part on a graph or chart that tells what each picture on a picture graph stands for
L
length How long something is. The distance from one point to another. Length is measured in units such as inches, feet, centimeters, etc.
less than Less than is used to compare two numbers when the first number is smaller than the second number3<6
less than Less than can be used to describe an action to mentally subtract 10 or 100 from a given number
line A line is straight. It has no beginning and no end
line plot A diagram showing data on a number line
M
making ten 9 + 1 makes 10.10 plus the 5 left over makes 15. A strategy that uses combinations of numbers that add up to ten
measuring tape A tool that can be used to measure length that is not flat or straight
meter A baseball bat is about1 meter long. A metric unit of length equal to 100 centimeters
meter stick A measuring tool that is 100 centimeters long
metric system A system of measurement based on tens. The basic unit of length is the meter
midnight12:00 at night
minute (min) A unit of time equal to60 seconds
minute hand The long hand on a clock
money Coins and bills used to pay for things
more Greater quantity or amount
more than More than can be used to describe an action to mentally add 10 or 100 more to a given number
N
nickel 5 ¢A coin worth 5 cents
noon 12:00 in the day
number A number indicates how many or how much. The number of objects can be named by the numeral 3 ***
number line A diagram that represents numbers as points on a line
number name The number name for 234is two hundred, thirty-four.A way of using words to write a number. (also known as word form)
numeral A symbol used to represent a number
O
odd number 9 is odd.An odd number cannot be shown as two equal parts. An odd number has 1, 3, 5, 7, or 9in the ones place
ones A single unit or object
P
p.m. The time between 12:00 noon and 12:00 midnight
pair A set of two things
partition Describes an action to divide shapes into smaller parts
pattern A repeating or growing sequence that follows a rule
penny A coin worth 1 cent
pentagon A shape with 5 straight sides
picture graph A graph that uses pictures or symbols to show data
place value HundredsTensOnes342The value a digit has because of its place in a number
Q
quadrilateral A shape with 4 straight sides
quarter 25 ¢A coin worth 25 cents
quarter hour 15 minutes = 1 quarter hour A unit of time worth 15 minutes
quarter of One of 4 equal parts
quarter past quarter past one15 minutes after the hour
R
rectangle A shape with 4 sides and 4 square vertices
rectangular prism A rectangular three-dimensional shape
regroup To rearrange the formation of a group
related facts Addition and subtraction facts that share the same numbers. (also known as fact family)
repeated addition Adding equal groups of objects to find the total amount of objects
rhombus A quadrilateral with all 4 sides equal in length
row A horizontal arrangement of numbers or information in an array or table
ruler A tool used to draw straight lines and measure length
S
side One of the line segments that makes a flat, two-dimensional shape
skip count5, 10, 15, 20Counting by a given number greater than 1
solid shape A shape that is not flat; an object that has three dimensions. (i.e., height, length, and width)
sort To group or organize according to shared attributes
sphere A solid shape with a curved surface
square A shape with 4 sides that are the same length and 4 right angles
standard form 234 A common way of writing a number using digits. (also known as base-ten numeral form)
subtract 5 –2 = 3 Take away, remove, or compare
sum The answer to an addition problem
survey Away to gather data by asking questions
T
tally chart A chart that uses tally marks to record data
tally mark A mark that shows a number or quantity. A tally shows one. A line through four tallies shows five
tens Something with ten parts or units
third of One of three equal parts
thirds The parts you get when you divide something into 3 equal parts
thousand A number equal to 10 hundreds
three-dimensional shape A solid shape that has length, width, and height
time How many seconds, minutes, hours, days, months, years, and so on. Time is shown on a clock or calendar
trapezoid A quadrilateral with 1 pair of parallel sides and 1 pair of sides that are not parallel
triangle A shape with 3 straight sides
two-dimensional shape A plane, flat shape that has length and width
U
unit What is used to measure the height, length, or heaviness of something
V
vertex The point where sides of a shape or angles meet. (plural -vertices)
vertical bar graph A graph that uses height of rectangles to compare data
W
whole All of an object, a group of objects, shape, or quantity
whole numbers Whole numbers are 0 and the counting numbers 1, 2, 3, 4, 5, 6, and so on
word form The word form of 234 is two hundred thirty-four.A way of using words to write a number. (also known as
number name)
XYZ
yardstick A measuring tool that is 3 feet or 36 inches long