Noun

• S: (n) addition, add-on, improver (a component that is added to something to improve it) "the addition of a bathroom was a major improvement"; "the addition of cinnamon improved the flavor"
• S: (n) 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"
• S: (n) addition, increase, gain (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"
• S: (n) accession, addition (something added to what you already have) "the librarian shelved the new accessions"; "he was a new addition to the staff"
• S: (n) addition (a suburban area laid out in streets and lots for a future residential area)
• S: (n) summation, addition, plus (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"