Margin

1. Something allowed, or reserved, for that which can not be foreseen or known with certainty.
2. To furnish with a margin.
3. Specifically: The part of a page at the edge left uncovered in writing or printing.
4. A border; edge; brink; verge; as, the margin of a river or lake.
5. Collateral security deposited with a broker to secure him from loss on contracts entered into by him on behalf of his principial, as in the speculative buying and selling of stocks, wheat, etc.
6. To enter in the margin of a page.
7. The difference between the cost and the selling price of an article.