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fly-by-night

fly-by-night

2 8.9
Not reliable and likely to disappear quickly, often for dishonest reasons
  • adjective
  • /ˈflaɪ baɪ naɪt/
  • Offensive
translation icon : sinvergüenza (informal, ofensivo)
  • Now is the time when fly-by-night, unregistered contractors will descend on storm-damaged areas, seeking to make a quick profit at the expense of homeowners.
  • fly-by-night operation
  • fly-by-night contractor
  • fly-by-night company

However, we need to help folks understand how to discern the fly by night charlatans from the effective treatment programs.

Examples

  • This is not some fly-by-night thing here.

  • I have complained to the landlord, and he had some fly-by-night pest control company come out.

    Blog text (3)
  • This is not a fly-by-night affair.

  • You 2 are just some fly-by-night operation looking to make a fast buck.

  • Baby, this ain't no fly-by-night operation.

  • Along comes this fly-by-night salesman and you're all taken in.

  • Of course, if they started as a fly-by-night operation, there probably wouldn't be much info out there.

    Blog text (13)
  • These aren't fly-by-night companies trying to do a scam here so they can collect a check if one of their employees dies.

  • "We don't want them to think that they're dealing with some fly-by-night operation."

    Fiction book (1994)
  • Many consumers have been scammed by fly-by-night companies that promise quick returns.

Synonyms

unreliable
vsfly-by-night
71 4.1

Not able to be trusted to work or be right

is also likely to disappear quickly, often for dishonest reasons
untrustworthy
vsfly-by-night
21 4.8

Not honest or reliable with promises

is likely to fail or vanish quickly for dishonest reasons
dodgy
vsfly-by-night
  • UK
13 8.2

Likely to be unsafe or untrustworthy

focuses more on quick failure or disappearing for dishonest intent
undependable
vsfly-by-night
3 4.7

Likely to fail or disappoint people

tends to fail quickly and may vanish for dishonest reasons
a bit sketchy
vsfly-by-night
  • Informal
1 8.6

A little suspicious and not easy to trust

is more extreme, likely to disappear fast and act dishonestly
untrusty
vsfly-by-night
  • Archaic
8.9

Not safe to depend on because they may fail or betray you

is prone to disappear or fail quickly for dishonest motives

Antonyms

473 2.3

Not likely to change and stays steady over time

47 2.3

A person or thing you can trust to do what they promise

How Reliable

trustworthy
88 2.1
reputable
53 4.2
unreliable
71 4.1
fly-by-night
  • Offensive
2 8.9
dishonest
128 2.5

Surface Forms

fly-by-night positive

Morphology

fly-by-night = fly + night (semi-transparent) = by + fly + night

The components are clear but the adjectival sense 'not reliable; likely to disappear' is idiomatic and not fully predictable from the words alone. [Postprocessing: moved 'by' from base_words to prefix]

Etymology

The word fly-by-night comes from the picture of someone who flies at night, slipping in and out while others sleep. That's why a fly-by-night company or person is called unreliable and likely to vanish or fail quickly.