Approve is a verb that refers to the act of officially signing off or sanctioning a particular item, task, conclusion, or result. In a more general sense it can be defined as to consider favorable, acceptable, or good such as in the following usage, “I approve of your decision to buy a hybrid automobile, as I think it is good for the environment.” It can also refer to, as in the initially mentioned definition above, to offer official consent or sanctioning to something, as in the example often heard by young grooms to be, “I approve of your marriage to my daughter.” The approval process in regards to project managing is one which will come up throughout the project. At the onset, those asked to take on a project will approve of the strategies to take to get to a conclusion, will approve of team members who may be assigned to assist, will approve the assignment of specific roles to specific team members. The noun form of this word, approval, is a word many of those participating in the development of a project look forward to hearing, as an approval is often granted by the assigning party when they have reviewed the deliverables and have deemed them acceptable.
This term is defined in the 3rd edition of the PMBOK but not in the 4th.