air, atmosphere, weather
氛 centers on the surrounding air or atmosphere, including its condition as weather. It refers to the invisible gaseous environment around us.
氛 combines 气 (gas, air) with 分, which likely contributes the sound and may suggest the idea of air dividing or spreading. The exact historical development is uncertain.
The outer 气 is a cloud of gas, and inside 分 looks like it's dividing or spreading. Picture the atmosphere as air that spreads everywhere, creating weather.
For フン, imagine a fun atmosphere at a party: fun -> フン, and the air is filled with excitement.
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