rockabye noun 1verb 1forms 4 noun1 •A soothing rocking motion.All the lullabies of the world suggest undulatory movements or rockabyes in the tree tops. — 1916 verb1 •To rock soothingly.“We have a Chopin player in the house,” he said. And with a tiny smile he rockabyed the opening phrase of the Ballade and turned his head to look straight at Katie. — 1952 formsrockabyed · rockabyeing · rockabying · rockabyes