means The command center where engineers and flight directors monitor and direct a spaceflight or other complex operation in real time.

from A plain English compound — 'mission' from the Latin 'mittere,' to send (the same root behind 'missile' and 'missionary'), and 'control.' The phrase crystallized in the American space program of the mid-20th century, where NASA's Mission Control Center in Houston turned the words into shorthand for a roomful of consoles and steady voices. From there it escaped orbit into everyday speech, so now any nerve center — a kitchen, a war room, a parent's command post — can earn the name.