addaddaddsaddedaddingverb (adds, adding, added)1to put something with something else: Mix the flour with the milk and then add the eggs. Add your name to the list.2to put numbers together so that you get a total: If you add 2 and 5 together, you get 7.Add $10 to the total, to cover postage and packing.oppositesubtract3to say something more: ‘Go away – and don't come back again,’ she added.add upto find the total of several numbers: The waiter hadn't added up the bill correctly.add up to somethingto have as a total: How much does all the shopping add up to?