from
Bouvier's Law Dictionary, Revised 6th Ed (1856)
NIL DEBET, pleading. The general issue in debt,6r simple contract. It is in
the following form: And the said D, by E F, his attorney, comes and defends
the wrong and injury, when, &c. and says, that he does not owe the said sum
of money above demanded, or any part thereof, in manner and form as the said
A B hath above complained. And of this the said C, D puts himself upon the
country." When, in debt on specially, the deed is the only inducement to
the action, the general issue is nil debet. Stephens on Pleading, 174, n.;
Dane's Ab. Index, h.t.