"mutually agreed upon," 1716, past-participle adjective from concert (v.).
Entries linking to concerted
concert v.
1690s, "to contrive, adjust;" 1707, "to contrive and arrange mutually," from French concerter and directly from Italian concertare "to bring into agreement," apparently from Latin concertare "to contend with zealously, contest, dispute, debate" from assimilated form of com "with" (see con-) + certare "to contend, strive," frequentative of certus, variant past participle of cernere "separate, distinguish, decide" (from PIE root *krei- "to sieve," thus "discriminate, distinguish"). Related: Concerted; concerting.