fly-by-night

[flahy-bahy-nahyt] / ˈflaɪ baɪˌnaɪt /

ADJECTIVE

unreliable and shady

Synonyms

STRONG

brief cowboy ephemeral passing temporary

WEAK

disreputable dubious evanescent fleeting here-today-gone-tomorrow impermanent irresponsible momentary not to be relied upon not to be trusted questionable shady shifty short-lived slimy slippery treacherous trustless undependable unprofessional unreliable unsure untrustworthy

Antonyms

STRONG

enduring lasting long permanent

WEAK

dependable reliable reputable responsible trustworthy

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

According to a federal complaint, 27-year-old Abdinajib Hassan Yussuf set up a fly-by-night autism center claiming to provide one-on-one therapy for autistic children.

From The Wall Street Journal • Mar. 8, 2026

A fly-by-night journalism outlet called BNN Breaking had used an A.I. chatbot to paraphrase an article from another news site, according to a BNN employee.

From New York Times • Jun. 6, 2024

There are just too many fly-by-night operations that either treat your personal data carelessly or, in some cases, just steal it.

From Seattle Times • Feb. 12, 2024

Experts say the problem is fueled by the ease of setting up a fly-by-night operation online to move goods.

From Washington Times • Jan. 1, 2024

Those jars were something you might expect to find in the basement of a fly-by-night medical school, not a house full of children.

From "Miss Peregrine's Home for Peculiar Children" by Ransom Riggs

fly-by-night

Example Sentences

Related Words