- not reliable or responsible, especially in business; untrustworthy: a fly-by-night operation.
- not lasting; brief; impermanent; transitory: a fly-by-night theater.
- a person or thing that is unreliable, especially a debtor who evades or attempts to evade creditors.
- a person regarded as a poor credit risk.
- unreliable or untrustworthy, esp in finance
- brief; impermanent
- an untrustworthy person, esp one who departs secretly or by night to avoid paying debts
- a person who goes out at night to places of entertainment
