Reboot was a term in computing for the process of restarting a working computer.
In 3188, after her red angel suit was damaged in a midspace collision, Michael Burnham requested a full system reboot from the suit's computer. As she descended to the surface of Hima, the computer kept saying, "Rebooting", as the process was occurring. Seconds from impacting the surface, the reboot completed with Burnham regaining control over the suit and softening her crash landing. (DIS: "That Hope Is You, Part 1")