1. The act of adding two or more things together; opposed to subtraction or diminution. This endless addition or addibility of numbers.
2. Anything added; increase; augmentation; as, a piazza is an addition to a building.
3. (Science: mathematics) That part of arithmetic which treats of adding numbers.
4. A dot at the right side of a note as an indication that its sound is to be lengthened one half.
5. A title annexed to a man's name, to identify him more precisely; as, john doe, Esq.; richard roe, Gent.; robert dale, Mason; thomas way, of new York; a mark of distinction; a title.
6. Something added to a coat of arms, as a mark of honor; opposed to abatement.
(Science: geometry) vector addition, that kind of addition of two lines, or vectors, ab and BC, by which their sum is regarded as the line, or vector, AC.
Synonym: increase, accession, augmentation, appendage, adjunct.
Origin: f. Addition, L. Additio, fr. Addere to add.