lullaby

 
Pronunciation: /ˈlʌləbʌɪ/

noun (plural lullabies)

  • a quiet, gentle song sung to send a child to sleep.

verb (lullabies, lullabying, lullabied)

[with object] rare
  • sing to (someone) to get them to go to sleep: she lullabied us, she fed us

Origin:

mid 16th century: from lull + bye-bye, a sound used as a refrain in lullabies; compare with bye-byes