From Longman Dictionary of Contemporary Englishcrooncroon /kruːn/ verb [intransitive, transitive] APMSAYto sing or speak in a soft gentle voice, especially about love Sinatra crooning mellow tunes ‘My child, ’ Sarah crooned. —crooner noun [countable]→ See Verb table
Examples from the Corpus
croon• Drake has low croon, duck a harsh wigeon-like quack: both make whistling sound in flight like Goldeneye.• She wandered around the tables, while crooning ''Embraceable You''.• Anyone playing the tape would hear Michael Jackson crooning in the exact digital quality they would hear on a purchased Thriller tape.• It was suffocating to sit between those merit was like being a fox in a bog while hounds crooned on either bank.• I move among the aisles and walkways, which are a scented, winking, shimmering, crooning riot of Christmas.• And a cassette deck crooning the blues and Bach.• A woman gently crooned the tune of a lullaby.• Lovely, lovely, she crooned to herself.• We hear her sobbing, lifting the baby up, crooning to it.• On the store speakers, Bing Crosby was crooning "White Christmas."• The vocals are strong, clear and smooth, crooning with the memory of what Sinatra was back in his day.Origin croon (1400-1500) Middle Dutch cronen 