Merriam-Webster Logo
SINCE 1828
Menu
×

An Encyclopædia Britannica Company

See What's Trending Now See More Trending Words
1

fly-by-night

play
noun \ ˈflī-bī-ˌnīt \

Definition of fly-by-night

1 :one that seeks to evade responsibilities and especially creditors by flight
2 :one without established reputation or standing; especially :a shaky business enterprise

Explore M-W

alt-59bab5dbb4997
Trending: 'Bodega' Startup Draws Criticism, Mockery
alt-59bff395cf879
What's Going On With 'Nonplussed'?
stylized-drawing-of-woman-pole-vaulting-across-gap-to-get-trophy
Challenging Vocabulary Quiz Returns!
image2143067130
9 Slang Words With Academic Origins

First Known Use of fly-by-night

1822

2

fly-by-night

adjective

Definition of fly-by-night

1 :given to making a quick profit usually by shady or irresponsible acts
2 :transitory, passing
  • fly-by-night fashions

See fly-by-night defined for English-language learners

First Known Use of fly-by-night

1914

FLY-BY-NIGHT Defined for English Language Learners

fly-by-night

adjective

Definition of fly-by-night for English Language Learners

  • : trying to make money quickly by using dishonest or illegal methods

Learn More about fly-by-night

  1. See words that rhyme with fly-by-night

Seen and Heard

What made you want to look up fly-by-night? Please tell us where you read or heard it (including the quote, if possible).

show hide

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!

WORD OF THE DAY

glabrous

play

smooth or hairless

Get Word of the Day daily email!

TRENDING NOW

  1. bodega "Don’t mess with the beloved bodega."

  2. carceral Of, relating to, or suggesting a jail or prison

  3. allegory No spoilers!

  4. hurricane 'A tropical cyclone'

  5. rescind To take away; cancel; repeal

SEE ALL

BROWSE DICTIONARY

fly-by-night

Test Your Vocabulary

Challenging Vocabulary Quiz Returns!

  • stylized-drawing-of-woman-pole-vaulting-across-gap-to-get-trophy
  • Which is a synonym of fuliginous?
Spell It

Can you spell these 10 commonly misspelled words?

TAKE THE QUIZ
Syn City

Test Your Knowledge - and learn some interesting things along the way.

TAKE THE QUIZ

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!

Words at Play

alt-59bff395cf879
What's Going On With 'Nonplussed'?

Its recent usage is hard to shrug off.

alt-59bad350d88f1
Welcome to the New Words

From 'hive mind' to 'sriracha'

image2143067130
9 Slang Words With Academic Origins

Class is in session.

image624847743
8 Foods Named After Real People

A delicious collection of eponymous foods

Ask the Editors

video-title-words-of-the-year-1066
Words of the Year: 1066

Or, Why Pig Meat is Called 'Pork' and Cow Meat is Called 'Beef'

payday
How Often Is 'Biweekly'?

Don't get us started on 'bimonthly'

video-irregardless-grammar-peeve-blend-of-the-synonyms-irrespective-and-regardless
Irregardless

It is in fact a real word (but that doesn't mean you should use it).

video-moose-goose-weird-plurals
Weird Plurals

One goose, two geese. One moose, two... moose. What's up with that?

Word Games

stylized-drawing-of-woman-pole-vaulting-across-gap-to-get-trophy
Challenging Vocabulary Quiz Returns!

No tricks, just difficult words.

Take the quiz
name-that-color-logo
Name that Color!

NEW! Additional colors! More obscure than before!

Take the quiz
Spell It
Spell It

Can you spell these 10 commonly misspelled words?

Take the quiz
Syn City
Syn City

Build a city of skyscrapers—one synonym at a time.

Play the game