A senior technician, or senior tech, is someone employed by a company, corporation or military organization who serves in a support capacity as a technician. This may include anything from mechanical engineering to computer operation to anything in the medical industry.
Senior tech is what actor Ashton Bingham is credited as in the "Human for a Day" episode of Supergirl. The senior tech was an employee of CatCo Worldwide Media in National City and was working the day an earthquake erupted through the city. CatCo CEO Cat Grant instructed him to get their computer servers back up and running so they could make a broadcast, but the young man did not possess the necessary skill to accomplish such a task. Ultimately, it was up to another employee, Winn Schott, to succeed where the senior tech had failed.