Margin

1. The edge of the paper that remains blank. The books I write always have a wide margin.
2. The edge of botanical leaves. Some plants have lobate margins.
3. A permissable difference; allowing some freedom to move within limits. There must be some margin of error.
4. The yield or profit; The selling price minus the cost of production. You should have at least a 20 percent margin on all products.
5. The edge defining inclusion in or exclusion from a set or group. She found herself just inside the margin of accepted society