1 to combine (two or more numbers or quantities) by addition
2 (transitive; foll byto)to increase (a number or quantity) by another number or quantity using addition
3 (transitive; often foll byto)to join (something) to something else in order to increase the size, quantity, effect, or scope; unite (with) ■ to add insult to injury
4 (intransitive; foll byto)to have an extra and increased effect (on) ■ her illness added to his worries
5 (transitive)to say or write further
6 (transitive; foll byin)to include
▷ noun
7 informalan instance of adding someone to one's list of contacts on some social networking sites ■ Thanks for the add!