William Oncken III
Who doesn't know a monkey, but the one that William Oncken III describes in Monkey Business (http://www.jaicobooks.com/) is different; it is at workplace.
A monkey, according to him, is the next move, initiative or action step in resolving a problem. "In most of your conversations during working hours, there comes a point where the dialogue breaks off and there is a next move." Monkey is what conventional managers call `assignment' says the author. Project, which is the vector sum of a lot of little assignments, is the `gorilla' - `a lot of little monkeys laid nose-to-tail'.