npignusA pledge; the deposit of a thing, or the transfer of possession of it. or dominion over it, as security for the performance of an obligation. The essential idea in the Roman and civil law is the putting of property, whether of a chattel, or land, or territorial jurisdiction (or servants or children, when they are regarded as property), under the hand of the creditor or pledgee as security, so that, although the right of the owner was not extinguished. the creditor or pledgee could enforce his claim without legal proceedings or any effort to gain possession: and this is also the essential idea in pawn and also in the strict use of pledge; while hypothec and mortgage imply that the owner retains possession, and that the creditor has only a right of action, or a right to demand possession in the contingencies agreed on.
Webster's Revised Unabridged Dictionary
Aptius uero per utriusque pignus et sanguinem amborum negotio consuli.