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How cool is coolth?

Q: My late mother’s family lived in suburban Philadelphia long before air conditioning. She and her relatives had a word, “coolth,” to describe the opposite of “warmth.” Did they make this up or has it existed before?

A: No, your mother’s family didn’t make it up. The word “coolth” (meaning coolness) has been around since the 1500s. And the high point of its popularity, according to Google’s Ngram viewer, was in the mid-20th century.

Interestingly, it’s been having a bit of a revival lately, according to Google searches, often in a newer, colloquial sense of the word.

The Oxford English Dictionary says “coolth” was formed “chiefly after warmth,” which first showed up in the 1100s. The OED points out a similar word in Old Dutch, cuolitha.

The earliest Oxford citation for “coolth” is from a 1547 Welsh-English dictionary in which oerfel, Welsh for cold, is defined as “coulthe” in English.

The OED, which describes “coolth” as chiefly literary, archaic, or humorous now, has examples of the usage from the 16th to the 21st century, including citations from Rudyard Kipling, J. R. R. Tolkien, Ezra Pound, and Seamus Heaney.

Here’s a literary example from Heaney’s 2001 poetry collection Electric Light: “The older I get, the quicker and the closer I hear those labouring breaths and feel the coolth.”

In recent decades, “coolth” has taken on a colloquial sense that the OED defines as the “quality of being relaxed, assured, or sophisticated in demeanour or style.”

The earliest example of this newer usage, which the dictionary describes as chiefly humorous, is from the May 26, 1966, issue of the San Antonio (Texas) Express: “In this marathon role she has wit, poise, warmth and a very taking coolth.”

The most recent citation is from Positively Fifth Street: Murderers, Cheetahs, and Binion’s World Series of Poker (2003), James McManus’s book about the poker championship in Las Vegas:

“My albeit progressive-bifocal shades suggest not feeble nearsightedness but its opposite—penetrating 20/20 vision to go with impenetrable coolth.”

We’ve found “coolth” in only a few standard dictionaries, defined as a pleasantly cool temperature or the quality of being fashionable.

We couldn’t tell from the OED examples of “coolth” in the thermometer sense whether the writers were using the word humorously or seriously.

However, Philip Durkin, writing in The Oxford Guide to Etymology, feels that some of these citations “are self-consciously humorous, especially from the late nineteenth century onwards.”

Although “coolth” has been used since the 16th century, Durkin says, the record of the usage is “rather patchy” and may be the result of repeated inventions of the word.

“There is probably not a continuous history of the usage, but rather a succession of separate formations of the word,” he writes.

R. Harald Baayen, in his 2003 paper “Linguistic Approaches to Morphology,” discusses “coolth” in writing about whether the English word ending “-th” is alive, dead, or something in between as an affix to form new words.

Baayen, whose paper was published in the book Probabilistic Linguistics, writes that the use of the affix “-th” in “coolth” points out the difficulty in judging whether a word element is, in linguistic terminology, productive, nonproductive, or semiproductive.

He says “coolth,” a term that was “once a nonce word made on analogy with warmth,” is now alive and well in both jocular and literal senses, “even though -th is one of the well-worn examples of a supposedly completely unproductive suffix in English.”

And if you’d like to read about a popular cousin of “coolth,” check out our “Birth of the cool” posting from 2010.

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