To hypothecate is to create security over property as collateral for a debt or obligation while leaving possession (and often use) of the asset with the debtor. In modern UK and Irish practice, the concept appears most clearly in secured lending, capital markets and shipping, and is usually implemented through specific security instruments rather than a standalone “hypothecation” document.In England & Wales and Northern Ireland, the idea of hypothecation is reflected in charges, mortgages and security interests under common law and statute (for example, under the Companies Act regimes on company charges), rather than being separately defined. It is often used descriptively in financial documentation to refer to charging or pledging assets, including re‑hypothecation of securities collateral by intermediaries.In Scotland, “hypothec” has an older, more technical meaning in relation to certain statutory or common law security rights, but in contemporary practice secured transactions are more commonly structured as fixed or floating charges or standard securities.In Ireland, the term is similarly used in finance and securities law as a descriptive expression for granting security over assets without transfer of possession, aligning broadly with practice in England & Wales and Northern Ireland.