What does ”that's saying something" mean?

I googled it, but I can't figure out anymore...

Does anyone can explain or rephrase it???

Thank you VERY much for your kind explanation!!!

I could easily understand the meaning.

I took note your sentence. And I will try using the phrase sometime.

May 23, 2019 10:20 AM
Comments · 3
“That’s saying something” is an idiomatic expression used to emphasize a point that you’re making. For example: “I am taller than my brother, and that’s saying something, because my brother is very tall.”
May 23, 2019

I feel as though the meaning is not clear, but perhaps simply to conclude a point made about something. It is a pretty ambiguous phrase that can be used in a variety of contexts. 

Some examples: 

"Annie even got up at 8am to help him move across town. Considering she is not a morning person, that's saying something." 

"Joe is always so positive about everything, that really says something about his character." 

"John apologized to her even though he did nothing wrong, and that says something." 

May 23, 2019

It could mean, it’s giving a suggestion, passing a message across, providing a hint, clue and so on. 

May 23, 2019
Language Skills
English, Japanese
Learning Language