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chancy trade or business with uncertain profitability
night entertainment business (e.g. hostess bar); nightlife business
フリーランスは水商売のようなものだ。
Freelancing is like a chancy business.
飲食業は水商売で、収入が安定しない。
The restaurant business is a chancy one, and income is unstable.
農家も作物の価格変動で水商売の厳しさを感じる。
Farmers also feel the harshness of a chancy business due to crop price fluctuations.