an agreement or compact, especially an official one.
2.
an agreement between the pope and a secular government regarding the regulation of church matters.
Origin: 1610–20; < French; replacing concordate < Medieval Latinconcordātum,Latin: neuter of concordātus, past participle of concordāre to be in agreement. See concord, -ate1
"agreement between church and state on a mutual matter," 1616, from Fr. concordat (16c.), from M.L. concordatum, noun use of L. concordatum, neut. pp. of concordare "agree," from concors (gen. concordis) "of one mind" (see concord).