Go out like a light and Go to sleep

Go to sleep and go out like a light are semantically related In some cases you can replace phrase "Go to sleep" with "Go out like a light", this phrases are similar.

Go to sleep verb - Prepare for sleep.

Go out like a light and go to sleep are semantically related in drop off topic. Sometimes you can replace phrase "Go out like a light" with "Go to sleep", this phrases are similar. informal substitute