'Promisor' definitions:

Definition of 'promisor'

(from WordNet)
noun
A person who makes a promise [syn: promiser, promisor]

Definition of 'Promisor'

From: GCIDE
  • Promisor \Prom"is*or\, n. (Law) One who engages or undertakes; a promiser. --Burrill. [1913 Webster]