Sleep like a top is an idiom that has been in use for hundreds of years; it is mostly used in British English. We will examine the meaning of the common idiom sleep like a top, where it came from, and some examples of its idiomatic usage in sentences.
To sleep like a top means to sleep soundly, to rest deeply. Sleep like a top is an idiom and a simile, which is a phrase used in a sentence that is a comparison of one thing with something else using the word like or the word as. One may be said to sleep like a top because he has a clear conscience, because he has put in a hard day of work, or simply because he practices good sleep hygiene. The expression sleep like a top has been in use since the 1600s and is an allusion to the fact that when a top is perfectly balanced when spinning, it stays in place. Related phrases are sleeps like a top, slept like a top, sleeping like a top.
I sleep like a top in the comfy, modern four-poster, and in the early morning watch a small mob of kangaroos outside in the garden, a mum with joey in pouch, another little chap just finding his feet, climbing the sandstone steps to nibble on the neatly tended lawn. (The Australian)
Eat peanuts like a squirrel, the tryptophan in peanuts will help you to sleep like a top! (Times of India)
I sleep like a top and have not ever felt in better health. (Financial Times)