1786, "office in a theater in which tickets are sold," from box (n.1) + office (n.). Box is attested from late 14c. in the specialized sense of "money box," especially one in which money is kept for some particular purpose; this was extended to "funds, money" before c. 1400. Box office in the figurative sense of "financial element of a performance" is recorded by 1904.
updated on October 22, 2022