Definition of lullaby noun from the Oxford Advanced Learner's Dictionary

 

lullaby

 noun
noun
BrE BrE//ˈlʌləbaɪ//
 
; NAmE NAmE//ˈlʌləbaɪ//
 
(pl. lullabies) Babies, Pieces of music
 
jump to other results
a soft gentle song sung to make a child go to sleep She sang her baby a lullaby. See related entries: Babies, Pieces of music Word Origin mid 16th cent.: from lull + bye-bye, a sound used as a refrain in lullabies; compare with bye-byes.
See the Oxford Advanced American Dictionary entry: lullaby