collatéral

Collatéral is a French term used as an adjective and noun. In general usage it denotes something located to the side or secondary. In specialized contexts it is employed to translate the English collateral, with related senses such as security or secondary relation. The word derives from Latin collateralis, meaning side by side; the feminine form is collatérale.

In finance, collateral refers to property pledged to secure a loan or obligation. The lender may claim the collateral if the borrower defaults. Common forms include real estate (mortgage), vehicles, or financial instruments such as stocks or bonds. Collateralization lowers lender risk and can influence loan terms and interest rates. Collateral can be held separately or cross-collateralized across multiple debts.

In medicine, collateral circulation describes alternative pathways of blood flow that develop to bypass a blocked vessel. Collateral vessels can be present naturally or form in response to ischemia, helping to preserve tissue perfusion. This phenomenon is relevant in conditions such as coronary artery disease, peripheral artery disease, and stroke.

In genealogy and law, collateral relatives are those who are not in the direct line of descent, such as siblings, aunts, uncles, cousins, and more distant kin. This usage contrasts with direct lineage (parents, grandparents, descendants). The term is often used in inheritance law and family trees.

Across fields, collatéral retains a core sense of being secondary, peripheral to a primary relation, obligation, or pathway.