why people feel down, they call the moon is blue moon?

Question

During the chinese mid autumn day, my friend who is work in overseas projec, she called the moon is blue moon.

Answer 1

due to the feelings that derive from the seasons it is just another belief that a blue moon cause one to feel depressed.

just like a "grey day".

Answer 2

The term Blue-moon has nothing to do with feeling down. A Blue-moon occurs whenever there are two full moons in a single month. A rare occurance.

The term 'Once in a Blue Moon" is used to express the rarity of someting. "She only asks for help once in a Blue Moon".

The term you are talking about is simply call "the Blues" or feeling "blue". It is referring to a sad or depressed state.

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