Team work.
I assume you are referring to the use of the term in relationship to goals and projects and not the original description of a stone marking off miles on a road. While it is not actually an antonym for a milestone, the opposite could be considered to be "setback".
A milestone is a significant step in the project life span. In general expect to see eight milestones per project as a broad rule of thumb. Most projects that recognize milestones will last more than a month, and probably less than five years. Each milestone will have at least one measurable, quantifiable, recognizable completion associated with it.
it is a definable, recognizable point in a projects time line.. E.G completion of "stage one" would be a milestone.. taken from the idea of stones used as way point indicators on on real world roads listing the distance from one town to another.. so in this instance a milestone is an indicator or some signifigant way point in a projects lifecycle. they can be used as a reference points in a project to help decide early on if a project is on time at a given reference. indicated as a dimond or dot in Microsoft project application program. Answer: A milestone is the beginning of a new phase or the completion of an important deliverable.
Download Milestone 1.9 (Super Tux 0.3.3): If you have a Windows OS:
Zero Milestone was created in 1923.
Milestone Systems was created in 1998.
Milestone Systems's population is 2,011.
Milestone Systems's population is 375.
Milestone S.r.l. was created in 1996.
Milestone Records was created in 1966.
Milestone Media was created in 1993.
Milestone Media ended in 1996.