grammarist.com

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An example:

Fly-by-night

Fly-by-night was originally a noun referring to one who goes out at night,1 usually for some wicked or mischievous purpose. It later gained a slang sense, referring to someone who gets out of a bill or a debt by fleeing in the middle of the night. From this derives the modern sense: today, fly-by-night is usually an adjective describing a fraudulent or dishonest business or money-making scheme. Fly-by-night operations tend to sell shoddy goods or to promise more than they can deliver, and quickly fold or disappear without providing refunds or returns on investment.