'lullaby' definitions:

Definition of 'lullaby'

From: WordNet
noun
A quiet song intended to lull a child to sleep [syn: lullaby, cradlesong, berceuse]
noun
The act of singing a quiet song to lull a child to sleep [syn: lullaby, cradlesong]

Definition of 'lullaby'

From: GCIDE
  • lullaby \lull"a*by\, n. [From Lull, v. t. ]
  • 1. A song to quiet babes or lull them to sleep; that which quiets. --Shak. [1913 Webster]
  • 2. Hence: Good night; good-by. [Obs.] --Shak. [1913 Webster]

Synonyms of 'lullaby'

From: Moby Thesaurus