On a day like this, the air is a thousand furry caterpillars crawling down your back. The sun shames you like a bad performance review, and all the envy you have ever felt creeps viscous from your skin and slinks to find the earth. Even the shadows of trees unwelcome you as though you had filled out paperwork in the wrong order. Your choice is to retreat to the hard artificial arctic of indoor air conditioning or to elongate yourself and allow the hot wet tongue of the dog star to lick you. Never mind how north you may be; your skin is in not the south but the sud, and it is torrific, horrific… sudorific.
If you’re in Canada, this word may be more familiar thanks not to the weather (which is only occasionally sultry) but to the toiletries: your antiperspirant (if you have one) says, on the French side, antisudorifique. Which can readily be anglicized as antisudorific, telling us that sudorific must mean perspirant and, from that, that sudor would seem to have to do with… sweat.
Which it does. It’s the Latin word for ‘sweat’. You may know it from the long and laborious medieval song “Olim sudor Herculis,” about the labours of Hercules, the title of which means “Once, the sweat of Hercules…”
But where does this word come from? Oh, that’s no sweat. No, wait, actually, it is. Or, anyway, it’s the same source as sweat, as scholars have found by poring over the historical record: sudor traces to Proto-Indo-European *sweyd-, which is also the source of Proto-Germanic *switjaną, which is the origin of, yes, sweat, and all the related words in other Germanic languages, such as German schwitzen and Yiddish shvitzn.
Well. This is the weather where we’re all shvitzers waiting for waiters to bring us spritzers (“sudo bring me a spritzer”). It’s not so terrific; it’s sudorific.