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

There is a fine line between success and failure in winter sports, where a few millimetres when landing difficult tricks on snow can make the difference between a medal or serious injury.

From BBC

They had to play this really fine line.

From Los Angeles Times

Australian Open chief Craig Tiley said Thursday it was "a fine line" between player promotion and privacy after top stars complained about backstage cameras at the Grand Slam, with Iga Swiatek comparing it to a zoo.

From Barron's

"It's not just as easy as raising the price. That's the thing that we have to measure very difficulty every day, there's a fine line between profitability, feasibility and what customers can and are willing to pay," he said.

From BBC

They reveal how he negotiated the fine line between autobiography and fiction and how closely he collaborated with editors, actors and experts in fields ranging from guns and counter-terrorism to pharmaceuticals and criminology.

From The Wall Street Journal