Hot Enough for You? Words for the Summer Heat

Remember to stay hydrated as you read these.

"Maggie had from her window, seen her stepmother leave the house—at so unlikely an hour, three o'clock of a canicular August…. It was the hottest day of the season…."
— Henry James, The Golden Bowl, 1904

Hearing one speak of the dog days of summer might make you think of a pooch panting with its tongue out during a heat wave. But despite the name, we can’t pin the sweltering August heat on man’s best friend.

The dog days get their name due to their association with the Dog Star, Sirius, found in the constellation Canis Major. Canicula is the Latin name for Sirius. The first visible rising of Sirius occurs during the hot stretch from early July to early September. The Greeks called this time of year hēmerai kynades, which the Romans translated into Latin as dies caniculares—the canicular days, or as we know them in English, "the dog days."


London set for hottest day of the year with 27C scorcher this week
— headline, News Shopper (, 18 May 2020

To scorch means to burn something so that it affects the color and texture of its surface. You might think of what happens when you leave an empty pan on the burner, but since it is also describes what happens when you get a sunburn, the use of scorcher for a day of extremely hot temperatures is more appropriate than you might think.

And while Friday will be a scorcher, Wisconsin has seen weather like this before. Southwest Wisconsin generally sees about three to seven days with a heat index higher than 95, and southeast Wisconsin averages one to three days a year with those high temperatures, according to the National Weather Service in Milwaukee.
— Elizabeth Dohms, Wisconsin Public Radio, 18 July 2019


Fervid can describe anything that gives off intense heat (as Nathaniel Hawthorne wrote of “the fervid coals of the hearth around which we were clustering” in The Blithedale Romance), but you are more likely to encounter the word today in descriptions of one’s intensity, enthusiasm, or zeal:

A fervid new push is being made to protect and restore previously clear-cut coast redwood forests after studies documented how they store more carbon than any other tree, a characteristic that researchers believe could be used as a bulwark against global warming.
— Peter Fimrite, San Francisco Chronicle, 30 Apr. 2020

The distinctions among fervid and its close relatives fervent and perfervid are subtle. Fervid suggests an emotion spontaneously and feverishly expressed, while fervent is more often used a passionate feeling delivered with sincerity and consistency (“a fervent advocate for the environment”) and perfervid for expressions that are overwrought or beyond what is necessary (“a preacher known for wild, perfervid orations”).


As it describes hell, Inferno is the title of the first part of Dante Alighieri’s 14th-century epic poem The Divine Comedy—the other parts being Purgatorio (Purgatory) and Paradiso (Heaven). In Dante’s version, hell is composed of nine concentric circles, each circle housing a certain category of sinner: the greedy, the lustful, the gluttonous, the wrathful, the fraudulent, etc. The ninth and innermost circle, representing treachery, is where Satan resides.

In the late 19th century, newspapers were using inferno to refer to a large fire giving off intense heat. That use perhaps picked up popularity in the 1970s with the release of the hit disaster film The Towering Inferno.


Quite often, it’s not the heat that gets you, it’s the humidity. When speaking of the weather, sultry describes air that is hot and humid. The obsolete English verb sulter is an alteration of the much more familiar word swelter, meaning “to sweat” or “to become faint from heat.”

2019 was India's seventh warmest year and Lucknow experienced hot, sultry and sweaty days. In the city, weather patterns all over the year took an unprecedented turn. In 2019, the average rainfall, the AQI, the heat and the winters were all way over the charts.
— Rishabh Pachory,, 14 May 2020

A synonym for sultry is muggy, which derives from an English dialectical word, mug, meaning “drizzle.” Unlike muggy, however, sultry has a sense pertaining to passion or desire, as in “a singer with a sultry voice.”


Calefaction is a rare word for the state of being warmed, deriving from Latin words for “to be warm” (calēre) and “to make” (facere). The verb chafe is an unlikely relative that took a path through Middle French and Middle English.

Calefaction is used almost exclusively in scientific contexts, though it occasionally turns up in more humorous uses:

Not that we'd ever dare question the sanity of having two Speaker Lapdesk SKUs, but you've got to admit Logitech hasn't really differentiated its new N550 -- a two-speaker, heat-shielded pad for treating your thighs with more kindness and less calefaction -- from its admittedly pricier predecessor.
— Vlad Savoy, Engadget, 7 Oct. 2010