a.

1. 並行的
2. 附屬的，附帶的
   digress into collateral matters

   扯到枝節問題上去

3. 旁系的；間接的
   A cousin is a collateral relative.

   表兄弟是旁系親屬。

4. 擔保的，有擔保的
   a collateral loan

   抵押貸款

n.

1. 旁系親屬[C]
2. 擔保品，抵押品[U][S1]
   He used his house as a collateral for the loan.

   他用房子作這筆貸款的擔保品。

n.

1. something pledged as security for repayment of a loan.
2. a person descended from the same ancestor as another but through a different line.

adj.

1. descended from the same stock but by a different line.
2. additional but subordinate; secondary.
3. situated side by side; parallel:
   collateral veins.