What is the difference between an expression, a saying, and a figure of speech?

Question

And under what category does "that's all she wrote" fall?

Answer 1

They can be used pretty much interchangeably. A saying generally carries the conotation that its a tradition or a phrase that is drawn from anther time or setting. A figure of speech is generally a phrase that may have a literal meaning far different from its figurative or intended meaning. And an expression would be anything else but like I said, they are very similar in meaning and can be used as synonyms. I wouls probably call, "That's all she wrote" s saying since it is probably derived from som other time or setting. An example of a figure of speech might be, "His goose is cooked." since it means something very different from its literal wording.

Answer 2

No difference.
An expression is a saying.....a saying is a figure of speech.... a figure of speech is an expression....
It's a neverending circle.
Therefore "that's all she wrote" falls under all 3.