| Noun | 1. | addition - a component that is added to something to improve it; "the addition of a bathroom was a major improvement"; "the addition of cinammon improved the flavor"additive - something added to enhance food or gasoline or paint or medicine afterthought - an addition that was not included in the original plan; "the garage was an afterthought" constituent, element, component - an artifact that is one of the individual parts of which a composite entity is made up; especially a part that can be separated from or attached to a system; "spare components for cars"; "a component or constituent element of a system" | |
| 2. | addition - the act of adding one thing to another; "the addition of flowers created a pleasing effect"; "the addition of a leap day every four years"step-up, increase - the act of increasing something; "he gave me an increase in salary" retrofit - the act of adding a component or accessory to something that did not have it when it was manufactured; "the court ordered a retrofit on all automobiles" subtraction, deduction - the act of subtracting (removing a part from the whole); "he complained about the subtraction of money from their paychecks" | |
| 3. | addition - a quantity that is added; "there was an addition to property taxes this year"; "they recorded the cattle's gain in weight over a period of weeks"accretion - something contributing to growth or increase; "he scraped away the accretions of paint"; "the central city surrounded by recent accretions" | |
| 4. | addition - something added to what you already have; "the librarian shelved the new accessions"; "he was a new addition to the staff"acquisition - something acquired; "a recent acquisition by the museum" | |
| 5. | addition - a suburban area laid out in streets and lots for a future residential area | |
| 6. | addition - the arithmetic operation of summing; calculating the sum of two or more numbers; "the summation of four and three gives seven"; "four plus three equals seven" | |