correus debendi

Etymology
First attested in 1668, in the singular on July 3rd and in the plural on December 19th; : +  (“of that which is to be owed”, the genitive singular of the neuter substantive of the future passive participle of, “I owe”) = “one jointly liable for something owed”.

Noun

 * 1)  A person   for a  with another or others; a  debtor; a.
 * 2) * 1668, July 3(1) and December 19(2), James Dalrymple, “Thomas Rue contra Andrew Houſtoun”(1) and “Mr. Alexander Seaton contra Menzies”(2) in The Deciſions of the Lords of Council & Seſſion I (Edinburgh, 1683), pages 548(2) and 575(2)
 * (1) He Suſpends on theſe Reaſons, that Thomas Rue had granted a general Diſcharge to Adam Muſhet, who was his Conjunct, and correus debendi, after the alleadged Service, which Diſcharged Muſhet, and conſequently Houstoun his Partner.
 * (2) The Pupil after his Pupillarity, had granted a Diſcharge to one of the Co-tutors, which did extinguiſh the whole Debt of that Co-tutor, and conſequently of all the reſt, they being all correi debendi, lyable by one individual Obligation, which cannot be Diſcharged as to one, and ſtand as to all the reſt.