# Sum vs Subadditive - What's the difference?

## As a noun sum

is noise (sound or signal generated by random fluctuations).

(of a function) such that the image of a sum is at most the sum of the images of the summands.

# sum

## English

(wikipedia sum)

### Etymology 1

(etyl) summe, from (etyl), from (etyl) summa, feminine of .

#### Noun

(en noun)
• A quantity obtained by addition or aggregation.
• The sum of 3 and 4 is 7.
• * Bible, Numbers i. 2
• Take ye the sum of all the congregation.
• (often plural) An arithmetic computation, especially one posed to a student as an exercise (not necessarily limited to addition).
• We're learning about division, and the sums are tricky.
• * Charles Dickens
• a large sheet of paper covered with long sums
• A quantity of money.
• a tidy sum
the sum of forty pounds
• * Bible, Acts xxii. 28
• With a great sum obtained I this freedom.
• A summary; the principal points or thoughts when viewed together; the amount; the substance; compendium.
• This is the sum of all the evidence in the case.
This is the sum and substance of his objections.
• A central idea or point.
• The utmost degree.
• * Milton
• Thus have I told thee all my state, and brought / My story to the sum of earthly bliss.
• (obsolete) An old English measure of corn equal to the quarter.
• * 1882 , James Edwin Thorold Rogers, A History of Agriculture and Prices in England , Volume 4, page 207:
• The sum is also used for the quarter, and the strike for the bushel.
##### Synonyms
* (quantity obtained by addition or aggregation) amount, sum total, summation, total, totality * (arithmetic computation) calculation, computation * (quantity of money) amount, quantity of money, sum of money * (summary) See summary * (central idea or point) center/centre, core, essence, gist, heart, heart and soul, inwardness, kernel, marrow, meat, nub, nitty-gritty, pith substance * (utmost degree) See summit * quarter
##### Derived terms
* a tidy sum * checksum * empty sum * nullary sum
* addition, summation: (augend) + (addend) = (summand) + (summand) = (sum, total) * subtraction: (minuend) ? (subtrahend) = (difference) * multiplication: (multiplier) × (multiplicand) = (factor) × (factor) = (product) * division: (dividend) ÷ (divisor) = (quotient), remainder left over if divisor does not divide dividend

#### Verb

(summ)
• * 2005 , .
• when you say that stability and change are, it's because you're summing them up together as embraced by it, and taking note of the communion each of them has with being.
• To give a summary of.
• ##### Synonyms
* (to add together) add, add together, add up, sum up, summate, tally, tot, tot up, total, tote up * (to give a summary of) See summarize

### Etymology 2

From the (etyl) , all of which have the core signification “pure”, used in elliptical reference to historical coins of pure gold.

*

#### Noun

• (en noun)
• The basic unit of money in Kyrgyzstan.
• The basic unit of money in Uzbekistan.
• ### Anagrams

* ----

• The square-root function is subadditive under addition because $\sqrt\left\{a+b\right\}\le\sqrt a+\sqrt b$.