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

They manage to walk a very fine line between sincere thanks and making fun of the ridiculousness of the situation.

From Salon

Still, you can’t guarantee virality: There’s a fine line between a “Spider-Man” triumph and a “Madame Web” tragedy.

From Los Angeles Times

There is a “fine line” between applying to too many jobs and looking complacent, she says.

From MarketWatch

There’s a fine line between compassion and pity.

From The Wall Street Journal

The therapist must tread a fine line between posing as a somewhat believable perpetrator and providing the patient with the opportunity for healing.

From Slate