CROON (2)

Croon, v. t. [imp. & p. p. Crooned (kro͞ond); p. pr. & vb. n. Crooning.] 1. 1. To sing in a low tone, as if to one's self; to hum.
Hearing such stanzas crooned in her praise. C. Bronté. 2. 2. To soothe by singing softly.
The fragment of the childish hymn with which he sung and crooned himself asleep. Dickens.