2 Answers

Definition of 'Break-Even Analysis'
An analysis to determine the point at which revenue received equals the costs associated with receiving the revenue. Break-even analysis calculates what is known as a margin of safety, the amount that revenues exceed the break-even point. This is the amount that revenues can fall while still staying above the break-even point.

http://www.investopedia.com/terms/b/breakevenanalysis.asp

In business, it's determining at what point you have recouped your (initial) investment to the point where you are not unprofitable nor profitable. It could apply to stocks also. Let's say you bought a stock at $10/ share but now it's $5/share. You would break even at $10 (excluding commissions, if there were any.)