Is ‘Set one’s hair on fire’ a popular English idiom?

Question

Yesterday’s (September8) New York Times carried an article titled ‘Setting Their Hair on Fire’ which was written by economist, Paul Krugman. It is followed by the following sentence:

“First things first: I was favorably surprised by the new Obama jobs plan, which is significantly bolder and better than I expected. It’s not nearly as bold as the plan I’d want in an ideal world. But if it actually became law, it would probably make a significant dent in unemployment.”

As ‘Set one’s hair on fire’ was unfamiliar expression to me, I searched on Google and found the following post on www.phrases. org:

HAIR ON FIRE - ".That odd phrase - believed to have originated among Navy aviators, intended to convey a sense of hair-raising urgency - quickly became the phrase of the day as this week's hearings began before the commission investigating events that led to 9/11...(Donald) Rumsfeld used it, saying such alarm wasn't uncommon: '...

From the above definition, I understand ‘Set one’s hair on fire’ means ‘a matter of emergency.' Am I right? The expression reminds me of Japanese popular saying, ‘焦眉の急 -urgency of scorching your eyebrows,’ to describe the urgent need.

Since Phrase Finder says ‘it’s odd phrase,’ I wonder how commonly ‘Set one’s hair on fire’ is used. Is it easily understood and widely spoken by both British and Americans today?

Answer 1

It's not at all common, nor would I necessarily believe it has origins in aviation slang.

Possibly because it's not common, it doesn't have a very fixed meaning either. Most often it's used in the sense that something sets your hair on fire if it's exciting (rather than requires urgent action). Less commonly, it's something you might do to attract attention, or simply a stereotypical example of something you really don't want to do

I think this expression would have died out completely, if it weren't for resonance with the much more common set the world on fire. Like that one, it's likely to be used in the negative (something that doesn't set your hair on fire is not very interesting).

Answer 2

Is this a popular English Idiom, easily understood by British and American people? probably not. It's definitely not common usage. I've never heard it before. But maybe that's me. So, to confirm my suspicions, I looked up Google Ngrams, and came up with:

"Set your hair on fire" can be seen as the green line, and that it's been used a little bit only. Not really popular.

What about "hair on fire?". The statistics shown on Google Ngrams show that it seems to be used quite a lot. But we must keep in mind that as Ngrams are searching books, fiction books could relate to incidents in the story where characters had their hair caught on fire. Still, I suppose there wouldn't be so many hair-burning stories.

So, "set one's hair on fire" is definitely not a popular usage idiom, but "hair on fire" is more common (although still not as popular as something like "my cup of tea"), and seems to be gaining in popularity.

Answer 3

It is not a common phrase. I do not think it is an idiom, per se. It is most likely a spontaneous phrasing. I have said similar things, in order to illustrate the idea of doing something absurd:

"I would not jump off a building," "I would not run my car off a bridge," "I would not stab myself in the eye with a knife," etc. It would simply mean "I won't do something absurd."