1. (a.) Coming from, being on, or directed toward, the side; as, collateral pressure.

2. (a.) Acting in an indirect way.

3. (a.) Related to, but not strictly a part of, the main thing or matter under consideration; hence, subordinate; not chief or principal; as, collateral interest; collateral issues.

4. (a.) Tending toward the same conclusion or result as something else; additional; as, collateral evidence.

5. (a.) Descending from the same stock or ancestor, but not in the same line or branch or one from the other; -- opposed to lineal.

6. (n.) A collateral relative.

7. (n.) Collateral security; that which is pledged or deposited as collateral security.