Operate too slowly. For example, My watch loses time, or This clock loses five minutes a day. This usage is always applied to a timepiece. [Mid-1800s]
Waste time, delay, as in We wanted to paint the entire porch today, but we lost time trying to find a color that matched the house. This expression is sometimes put negatively as , meaning "act immediately" or "not delay," as in We must lose no time in getting him to the hospital. [Late 1500s] Also see make up for lost time.