Definition of add up

The origin of the phrase "add up" can be traced back to the Middle English verb "summen," which means "to make a sum or total." This word, in turn, is derived from the Old French word "sommer," which also means "to summon" or "to call together." The idea behind "add up" is to gather or collect numeric quantities and combine them to obtain a total, which can be seen as a way of "calling" these quantities together to produce a sum. This usage of "summon" to mean "add" became widely used in the 14th century, and the phrase "add up" first appeared in print in the 1530s in the English language. In modern times, the phrase "add up" is commonly used in various contexts such as mathematics, accounting, and finance, where the calculation of totals is an essential part of the work involved.