There are many different ways to say that something or someone has been "turned off." Some synonyms might include "shut down," "powered off," "switched off," or "disconnected." Other options could be "unplugged," "cut off," "deactivated," or "disabled." Depending on the context, variations like "quenched," "extinguished," "dimmed," or "muted" might also work. In some cases, it might be more appropriate to use a phrase instead of a single word, like "put to rest," "terminated," or "ended." Ultimately, the right synonym will depend on the specific situation and the nuances of meaning that you want to convey.