Reference
Math Terms Glossary for Parents
Homework often uses vocabulary that's easy to forget if it's been a while. Plain-English definitions for the terms that come up most:
Sum
The answer to an addition problem. The sum of 4 and 5 is 9.
Difference
The answer to a subtraction problem. The difference between 9 and 4 is 5.
Product
The answer to a multiplication problem. The product of 4 and 5 is 20.
Quotient
The answer to a division problem. The quotient of 20 divided by 4 is 5.
Remainder
What's left over when a number doesn't divide evenly. 17 ÷ 5 is 3, remainder 2.
Place value
The value of a digit based on its position in a number. In 352, the 3 is worth 300 (hundreds place), not just 3.
Carrying (regrouping)
Moving a value into the next column during addition when a column's total is 10 or more, as in 47+26.
Borrowing (regrouping)
Taking a value from the next column during subtraction when the top digit is smaller than the bottom one, as in 82−35.
Fact family
A group of related facts built from the same three numbers, like 4+5=9, 5+4=9, 9−4=5, and 9−5=4.
Number bond
A pair of numbers that combine to make a target number — the "bonds of 10" are 1+9, 2+8, 3+7, 4+6, and 5+5.
Estimate
A reasonable approximate answer found by rounding, used to sanity-check whether an exact answer seems right.
Whole number
A number with no fraction or decimal part — 0, 1, 2, 3, and so on.
Digit
A single numeral from 0–9. The number 352 has three digits.
Even / odd number
An even number divides evenly by 2 with no remainder (4, 18, 100); an odd number doesn't (3, 17, 99).
Multiple
The result of multiplying a number by a whole number. 15 is a multiple of 5, because 5×3=15.
Factor
A number that divides evenly into another. 5 is a factor of 15, because 15÷5 has no remainder.
Array
Objects arranged in equal rows and columns, often used to show multiplication visually — 4 rows of 3 dots represents 4×3.
Mental math
Solving a problem in your head, without paper or a calculator, often using shortcuts rather than the written method.
Fluency
Being able to recall a fact or solve a problem quickly and accurately, without consciously working through every step.
Seeing a term above that's still fuzzy for your child specifically? Our practice guide and word problems guide both use these terms in context, worked through step by step.