Meaning & use
sleeping like a baby
Last updated
Meanings
phraseidiominformal
Sleeping very deeply and peacefully, without waking up.
Grammar: It is used after a form of 'be' or as a participle: 'He was sleeping like a baby.' You do not change the words inside the idiom.
Patterns
- be sleeping like a baby
- sleep like a baby
After the long hike, he was sleeping like a baby by nine o'clock.
The baby had a full feed and now she is sleeping like a baby.
I took some medicine for my cold and slept like a baby all night.
phraseidiominformalfigurative
Working or running very smoothly and without problems, especially of a machine or system.
Grammar: This figurative use is common in informal speech about engines, computers, or projects.
Patterns
- be running like a baby
- go like a baby
Since the repair, the old engine has been running like a baby.
The new software update installed cleanly, and now the system is going like a baby.
Common combinations
- sleep like a baby
- On holiday I always sleep like a baby.
- be sleeping like a baby
- Don't call him now — he's sleeping like a baby.
- run like a baby
- The car is old but it still runs like a baby.
Synonyms and how they differ
- sleep soundly
- This is a more neutral, slightly more formal way to say someone sleeps deeply, and it does not carry the warm, informal feeling of the idiom.
- be out like a light
- This informal idiom means you fell asleep very quickly, often suddenly, rather than that your sleep is peaceful and deep.
Opposites
Commonly confused: sleeping like a baby or sleep like a log?
sleeping like a baby vs sleep like a log
This idiom also means to sleep very deeply, but it sounds heavier and less gentle than 'sleeping like a baby'.
Practice
Which sentence uses 'sleeping like a baby' correctly?
Choose one answer.
The idiom describes deep, peaceful sleep, so option A fits. Option B is wrong because worrying all night would not produce peaceful sleep. Option C is wrong because the idiom is normally used with singular subjects or in a fixed way; 'they were sleeping like a baby' sounds odd. Option D is wrong because 'to finish my homework' shows purpose, not the meaning of the idiom.
Make it your own
Write a sentence using “sleeping like a baby”, then check it and compare it with the examples above.