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

So far, Washington's outgoing Mayor Muriel Bowser has walked a fine line between defending the city's interests and cooperating with Trump on certain projects.

From Barron's • May 19, 2026

“You walk a fine line not pushing the next generation to come on board, while trying to develop a passion for the family business,” Lisa says.

From The Wall Street Journal • May 10, 2026

Global air carriers are walking a fine line between ongoing strong demand for air travel and rising costs — fuel is second only to labor costs in the airline industry.

From MarketWatch • Apr. 28, 2026

As to the famous fine line between stupid and clever, the stupidity and the cleverness are all but inextricable, and to the point.

From Los Angeles Times • Feb. 20, 2026

The fine line between safety and danger was probably all about lucky connections.

From "A Thousand Sisters" by Elizabeth Wein