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

Stories about friendships between animals must walk a fine line between the sweet and the saccharine.

From The Wall Street Journal • Mar. 20, 2026

Moore has also tried to walk a fine line on the LAFD’s after-action report, which was meant to spell out mistakes and suggest measures to avoid repeating them.

From Los Angeles Times • Feb. 24, 2026

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 • Feb. 5, 2026

“This is a fine line between boosting economic growth and boosting inflation.”

From MarketWatch • Jan. 26, 2026

Daddy follows and I cringe at the fine line of mud on the back of his shoe.

From "The Help" by Kathryn Stockett