Letters that make quack-quack
a, k, c, q, u are letters that make 'quack-quack'
a, k, c, q, u are letters that make 'quack-quack'
1 possible definitions for 'quack-quack'
Under this definition, quack-quack is a noun and has the following properties:
'quack-quack' can be a type of duck.