Goldwynisms are funny phrases or statements that were said by Samuel Goldwyn, a famous American film producer in the mid-20th century. Goldwyn was known for saying things in a very unique and unusual way that often made people laugh or scratch their heads in confusion.
For example, when asked why he thought his movies were so successful, he famously said: "Pictures are made to be seen, not to be believed." And when he was told that a particular script was "not that good," he replied: "It's not even 'not that good'."
Basically, Goldwynisms are just funny sayings or phrases that we all laugh at because they are so strange and unexpected. It's like when your dad tells a joke that's so bad it's good- Goldwynisms are just like that, but they come from a famous Hollywood producer.