1. Literally, to begin sleeping. I'm sorry, but Kristin has already gone to sleep—can I take a message? I plan to go to sleep early after staying up so late last night.

2. Of a limb or other part of the body, to lose feeling, usually because one has sat or leaned on it for too long. Ugh, wait a second, my foot has gone to sleep—I can't get up just yet.

3. slang Die; drop dead. Used as an imperative indicating contempt or dismissal. Go to sleep, Warren. No one cares.