con·cert pitch • n. Mus. a standard for the tuning of musical instruments, internationally agreed upon in 1960, in which the note A above middle C has a frequency of 440 Hz. ∎ fig. a state of readiness, efficiency, and keenness.
"concert pitch." The Oxford Pocket Dictionary of Current English. . Encyclopedia.com. (November 19, 2018). https://www.encyclopedia.com/humanities/dictionaries-thesauruses-pictures-and-press-releases/concert-pitch
"concert pitch." The Oxford Pocket Dictionary of Current English. . Retrieved November 19, 2018 from Encyclopedia.com: https://www.encyclopedia.com/humanities/dictionaries-thesauruses-pictures-and-press-releases/concert-pitch