Definition of break even
We can be in profit (+), we can be in loss (-) and we can be break even (+/- 0). Whether it's a poker night, a business project, a casino night, when we talk about break even, we mean that with our winnings and losses or winnings and expenses, we arrive at 0, so no profit or loss. Break even sessions in poker can be numerous. "I was a loser in my session before I won this huge pot; now I'm break even and I'm going to take a break.
Break even games
When we talk about break even, we can also talk about the types of poker games. As a winning player, you will always want to make EV+ plays (long term winning plays), but sometimes you will make plays that are break even, meaning that they have a long term expectation of winning 0. This is usually the case with bluffs on the river. After analysis, you realize that not making or making a bluff will, in the long run, be a break even play. Whether or not you bluff in this situation will be irrelevant to your long term winnings.