| 1. | 
	 (noun) 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"   | 
	
	
	
	
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	 Related Words: fluoridation, fluoridization, increase, step-up | 
	
        
	
	
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	 Antonyms: subtraction | 
	
	
	
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         | 2. | 
	 (noun) 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"   | 
	
	
	
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	 Synonyms: improver | 
	
        
	
	
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	 Related Words: additive, afterthought, annex, annexe, attachment, component, constituent, element, elongation, extension, softener, wing | 
	
        
	
	
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         | 3. | 
	 (noun) a suburban area laid out in streets and lots for a future residential area   | 
	
	
	
	
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	 Related Words: suburb, suburban area, suburbia | 
	
        
	
	
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         | 4. | 
	 (noun) 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"   | 
	
	
	
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	 Synonyms: gain, increase | 
	
        
	
	
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	 Related Words: indefinite quantity | 
	
        
	
	
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         | 5. | 
	 (noun) something added to what you have already; "the librarian shelved the new accessions"; "he was a new addition to the staff"   | 
	
	
	
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	 Synonyms: accession | 
	
        
	
	
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	 Related Words: acquisition | 
	
        
	
	
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         | 6. | 
	 (noun) 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"   | 
	
	
	
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	 Synonyms: plus, summation | 
	
        
	
	
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	 Related Words: arithmetic operation | 
	
        
	
	
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