fine line

American  

[fahyn lahyn] / ˈfaɪn ˈlaɪn /

noun

1. a small, barely perceptible difference.

   There's often a fine line between helping and interfering.

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idioms

1. walk a fine line,

   1. to act carefully in order to avoid the wrong outcome or maintain a delicate balance.

      Moderators walk a fine line between censorship and protecting their site's users.

      I had to walk a fine line between maintaining the peace and doing my job.

   2. to act in a way that risks a disastrous outcome.

      You’re walking a fine line, buddy—if you don’t start watching your mouth, you’ll lose the respect of your kids.

Etymology

Origin of fine line

First recorded in 1845–50

Example Sentences

See Examples For:

fine line

With AI, they are still walking that fine line.

From Barron's ● Sep. 15, 2026

For card issuers, it means walking a fine line between stopping people from milking perks in a way that wasn’t intended, while also being careful not to upset some of their most valuable customers.

From The Wall Street Journal ● Aug. 31, 2026

“It’s a fine line between being melodramatic and being truthful” in birth and death scenes, the Southern California native tells The Envelope.

From Los Angeles Times ● Aug. 18, 2026

"He's navigating a very fine line between keeping his constituents happy and not angering or alienating President Trump," he told the BBC.

From BBC ● Aug. 10, 2026

Her name had been painted with great skill in red paint and outlined with a fine line of cream in a way that he would never have managed.

From "The Book of Dust: La Belle Sauvage" by Philip Pullman