I am having one of those days when I sharply and sincerely regret getting out of bed. Comprising a soaking wait at the bus stop, a tooth injury, a soggy two-hour commute into work, a setback at the office and the discovery that a leaky roof had caused rain to flood my garage, I am having a pretty awful day. And it’s only 2pm.

Usually, my style is to get angry, then determined, then dismantle all the problems with my bare hands and smash them together until they’re fixed. Today, though, I won’t do much about any of this. I’m enervated. I’m deflated. I’m blue.

Blue is a funny word. When the color is used in marketing, it evokes a strong, regal, trustworthy feel and it is the world’s favorite color. Yet when we talk about the word blue, it takes on a dour or sad meaning.

No one is exactly sure how English picked up the concept of “feeling blue,” though it’s been with us since the 1600s. Mariners say it refers to the practice of flying a blue flag after the death of a captain. Vikingologists fancy that Thor would turn the sky blue as an expression of his sad or angry feelings. The former explanation gets more ridiculous the more you think about it.

I like to think it’s related to staring at the sky as a response to melancholia, making shapes in the clouds and letting our subconscious work on our problems while we ponder something else. Science says we may even be programmed to sit, zonked, in the sun when we are sad, in case our malaise is related to Vitamin D deficiency.

Blue is also synonymous with that which is wrong and naughty. Blue notes in music are ones that are slightly off-pitch, and their name comes from the blues musicians who played them. The blues is thought to share its root with our sad kind of blues but other historians have pointed out that in jazz-era black-American slang, the “blue devils” or “blues” can also refer to hallucinations brought on by alcohol withdrawal. My uncle is fond of blue, or off-color, jokes; the etymology of which is very much still in dispute.

Then there is the good old Aussie blue. Meaning an argument or fight, often one you’re trying to play down for the benefit of not getting into trouble with the missus, a blue seems to have appeared from nowhere etymologically, but is probably connected with the phrase “argue until you’re blue in the face.”

Which is probably what I’ll have to do to get the landlord to fix the leak. But not today.