“A simple traditional song or poem for children” (Oxford Dictionaries)
The Difficulty of Defining Nursery Rhymes
Hey diddle diddle,
The cat and the fiddle,
The cow jumped over the moon;
The little dog laughed
To see such sport,
And the dish ran away with the spoon
Nursery Rhymes and (cynical) jokes
– rebellion against authority
- releasing taboos in polite society