- Addams crater
- add animation
- add a word(s) to explain classics
- add charges, amend a prosecution, withdraw a prosecution
- added ordering
- added scenery
- added tables
- addend
- addendum cone
- addendum envelope
- Addendum on Complete Literature Works of Tang Dynasty
- Addendums of Notes on Song Dynasty Poetry
- adder
- adder-accumulator
- adder's tongue family
- adder subtracter
- addible
- addiction
- addiction treatment centre
- addictive behavior
- addictive behavior and behavioral addiction
- addictive disorder
- Addict to Love
- ADDIE model
- ADDIE模型