Citations:unadd

Verb: "to remove something after it has been added"

 * 2007, Philip Purser, Natural Terrariums, T. F. H. Publications (2007), ISBN 9780793828913, page 82:
 * Adding fertilizer to a terrarium is a lot like adding salt to a recipe: Once you've added too much, you can't unadd it, and you've likely ruined the recipe!
 * 2011, Tim Phillips, Talk Normal: Stop the Business Speak, Jargon and Waffle, Kogan Page Limited (2011), ISBN 9780749463649, page 50:
 * Collaboration tends to be a one-way street: once you've added people to the project, it's hard to unadd them.
 * Collaboration tends to be a one-way street: once you've added people to the project, it's hard to unadd them.

Verb: "to separate the sum of two or more added numbers (?)"

 * 2013, Colm Mulcahy, Mathematical Card Magic: Fifty-Two New Effects, CRC Press (2013), ISBN 9781466509764, page 127:
 * Now I want you to take off as many cards you wish–I suggest any number between two and ten–and then add their values. I'll then unadd them, sight unseen, and tell you what you have just from know the total.

Verb: "to subtract"

 * 2000, James W. Heddens & William R. Speer, Today's Mathematics, John Wiley (2000), ISBN 9780471391449, page 124:
 * Similarly, we can add and then "unadd" or subtract.