collateral
Pronunciation: /kəˈlat(ə)r(ə)l/
noun
adjective

Origin:
late Middle English (as an adjective): from medieval Latin collateralis, from col- 'together with' + lateralis (from latus, later- 'side'). collateral (sense 1 of the noun) (originally US) is from the phrase collateral security, denoting something pledged in addition to the main obligation of a contract