summand

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From sum +‎ -and.

summand (plural summands)

1. Something which is added or summed.

   In the expression 1+2=3, the summands are 1 and 2.

One says that ${\displaystyle x}$ is a summand of ${\displaystyle z}$ if there exists some ${\displaystyle y}$ such that ${\displaystyle x+y=z}$ (where ${\displaystyle x}$, ${\displaystyle y}$, and ${\displaystyle z}$ are all understood to be objects of a certain type, such as numbers, vectors, etc., which the context makes clear). For instance, working over the positive integers, 3 is a summand of 5 (because 3 + 2 = 5), but 7 is not a summand of five.

• addend

• term

Other terms used in arithmetic operations:

Advanced hyperoperations: tetration, pentation, hexation