(informal) A person who spends a lot of time sitting at a desk.
2007, Marlene L. Woelm, The Ghosts on 87th Lane, Llewellyn, →ISBN, page 84:
My receptionist job had turned me into a desk potato, so I began walking Pete every night in the fall of 1979 to provide the exercise my body was craving.
2010, Phil Trupp, Ruthless: How Enraged Investors Reclaimed Their Investments and Beat Wall Street, John Wiley & Sons, →ISBN, page 236:
I knew the job of writing the book would turn me into a desk potato.
2015, Sifu Slim, Sedentary Nation: The Answers Are Found in 1910[1], →ISBN:
Compare that to a desk potato whose gaze is focused on the screen, inputting data into QuickBooks or Excel.