A technique for studying the relationship among fixed costs, variable costs, sales volume, and profits. It is also called cost/volume/profit (C/V/P) analysis.
An analysis of the level of sales at which a project would make zero profit.
An analysis of the level of sales at which a project would make zero profit. 
Is the analysis of the level of sales at which a project would just break even. This may or may not include opportunity cost of capital.
Break-even analysis:
The analysis of the point in time when an investment will be repaid by the benefits estimated in a cost benefit analysis.
An analysis of the level of sales at which a project would make zero profit.
A measure used to determine the approximate sales volume required to cover the costs associated with