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1. A component that is added to something to improve it
   "the addition of a bathroom was a major improvement";
   - add-on, improver
    
2. 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"
    
3. A quantity that is added
   "there was an addition to property taxes this year";
   - increase, gain
    
4. Something added to what you already have
   "he was a new addition to the staff";
   - accession
    
5. A suburban area laid out in streets and lots for a future residential area
    
6. The arithmetic operation of summing; calculating the sum of two or more numbers
   "the addition of four and three gives seven";
   - summation, plus

Sounds like: edition

Derived forms: additions

Type of: acquisition, arithmetic operation, burb [N. Amer, informal], component, constituent, element, increase, indefinite quantity, step-up, suburb, suburban area, suburbia

Antonym: subtraction

Encyclopedia: Addition