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

Carriers are walking a fine line between strong demand and rising costs, and they’re responding the only way they can in the short term: with fewer flights.

From MarketWatch • Apr. 22, 2026

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

From The Wall Street Journal • Mar. 20, 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

Tina says there's also a fine line between refreshing and overdoing it as "very aggressive ice exposure can irritate sensitive skin or trigger rosacea, so keep it gentle".

From BBC • Feb. 16, 2026

In competition, we always performed the skills we’d practiced and mastered in the gym, because as any gymnast can tell you, there’s a fine line between being courageous and ending up with a major injury.

From "Courage to Soar" by Simone Biles