collateral

noun

• 1something pledged as security for repayment of a loan, to be forfeited in the event of a default.

• 2a person having the same descent in a family as another but by a different line.

adjective

• 1additional but subordinate; secondary:the collateral meanings of a word
• used euphemistically to refer to inadvertent casualties among civilians and destruction in civilian areas in the course of military operations:munitions must be able to destroy the target without causing collateral damage collateral casualties

• 2descended from the same stock but by a different line:a collateral descendant of George Washington

• 3situated side by side; parallel:collateral veins