sum is on the Academic Word List.

Pronunciation

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Singular
sum

Plural
sums

  1. (countable) A sum is an amount of money, usually a large amount.
    The company had been spending large sums on publicity and advertising.
    It allows the corporation to pay its workers a lump sum of up to £37,000 on leaving.
  2. The sum is the total of adding or subtracting several numbers or amounts.
    The total output doesn't equal the sum of the inputs because the system is not 100% efficient.
    The sum of the three numbers will always equal 10.
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Plain form
sum

Third-person singular
sums

Past tense
summed

Past participle
summed

Present participle
summing

  1. If you sum up, you conclude or bring together the main points.
    She sums up the situation by saying that the new family is never the same as the biological family.

Synonyms

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