python what does def mean code example

Example 1: python funtion

def nameOfFunction(something):
  	return something

Example 2: what does * mean in python in functions

>>> numbers = [2, 1, 3, 4, 7]
>>> more_numbers = [*numbers, 11, 18]
>>> print(*more_numbers, sep=', ')
2, 1, 3, 4, 7, 11, 18