Definition of sum
(Entry 1 of 3)
1
: an indefinite or specified amount of money
2
: the whole amount : aggregate
3
: the utmost degree : summit
reached the sum of human happiness
4a
: a summary of the chief points or thoughts : summation
the sum of this criticism follows— C. W. Hendel
b
: gist
the sum and substance of an argument
5a(1)
: the result of adding numbers
the sum of 5 and 7 is 12
(2)
: the limit of the sum of the first n terms of an infinite series as n increases indefinitely
b
: numbers to be added
broadly
: a problem in arithmetic
c(1)
: disjunction sense 2
(2)
: union sense 2d
in sum
: in short : briefly
sum
verb
summed; summing
Definition of sum (Entry 2 of 3)
: to reach a sum : amount
sum
noun (2)
plural sums
Definition of sum (Entry 3 of 3)
the basic monetary unit of Uzbekistan — see Money Table
Keep scrolling for more
Keep scrolling for more
Keep scrolling for more
Keep scrolling for more
Test Your Vocabulary
Name that Thing: Flower Edition

 Name that flower
Test your knowledge  and maybe learn something along the way.
TAKE THE QUIZSpell words. Make bears.
TAKE THE QUIZLove words? Need even more definitions?
MerriamWebster unabridged
Words at Play
Ask the Editors
Share sum
Time Traveler for sum
The first known use of sum was in the 14th century
See more words from the same century