add

Add is a verb with several closely related meanings centered on combining, increasing, or including.

In everyday and formal usage, to add means to join one thing to another, to attach or append something, or to include it in a calculation or list. It can also mean to increase the amount, degree, or size of something, as in adding more ingredients or adding a new member to a group. Idiomatic uses include phrases like “to add insult to injury” or “to add up,” meaning to be coherent or to make sense.

In mathematics, add refers to the operation of addition, the process of combining two or more numbers or quantities to produce a sum. The operation is binary and associative, commutative, and has the identity element zero. The result of adding numbers is called the sum.

In computing and computer science, add commonly denotes the arithmetic addition performed by the plus operator or an add function. In many programming languages, the plus sign performs numeric addition and, depending on language rules, may perform string concatenation as well. In databases and spreadsheets, addition is used to compute totals, often through dedicated functions such as SUM or through arithmetic expressions.

Etymology traces add back to Old English addian, related to Latin addere, from ad- ‘toward’ + dare ‘to give,’ reflecting the sense of bringing quantities together.

See also: addition, arithmetic, sum.