The verb form of the word is "sleep," which means to rest or take a break from activity. The noun form, "sleep," refers to the period during which someone is inactive and their body is at rest.
Usage examples
I was sleeping when the thunderstorm started.
The baby is finally sleeping through the night.
I had trouble sleeping because of the noisy neighbors.
She was sleeping like a log and didn't hear her phone ringing.
There is also a chance that he is waking in the night from being disrupted in sleep in the day. (babywisemom.com)
She might only realize afterward that she «paid» for a full night of sleep with a breast infection or the return of her period (and hopefully not an unwanted pregnancy). (amotherinisrael.com)
Prepare your baby for sleep with a regular bedtime ritual, which you can do in fifteen minutes. (newkidscenter.com)