countersecurity

counter- +‎ security

countersecurity (countable and uncountable, plural countersecurities)

1. A commitment to guarantee the security (property or bonding in securing a loan) of someone who has become security for another.
   • 1885, Maryland. Court of Appeals, Alexander Contee Magruder, Oliver Miller, Maryland Reports, page 15:

     This is an appeal from an order of the Orphans' Court of Frederick County requiring the appellant, the surviving executor of John Sifford, deceased, to give countersecurity.

   • 1894, Great Britain. Royal Commission on Historical Manuscripts, The Manuscripts of the House of Lords, 1692-1693, page 2:

     Sir John's executors, under colour of some countersecurities given to Sir John and some assignments of judgments, unjustly compelled Sir Arthur to pay 1,600l. and upwards for debts from which Sir John had discharged him.