In a Word: What’s So Casual about Casualties?

Senior managing editor and logophile Andy Hollandbeck reveals the sometimes surprising roots of common English words and phrases. Remember: Etymology tells us where a word comes from, but not what it means today.

Whenever I hear some newscaster talk about casualties of a battle, I see that word casual buried in there and am left with an uncomfortable wonder about how the two words are connected. What’s so casual about casualties anyway?

A lot, it turns out — at least etymologically.

Both words trace back to the Latin verb cadere “to fall.” From the past participle stem of cadere we get the Latin noun casus, literally “a falling” but used to mean “an accident, occurrence, event,”  (It also gave us the word case.) And then in Late Latin, we got the adjective form casualis “occurring by chance,” and now we’re getting close.

Casualis became the Old French casuel, which became casual in Late Middle English. The sense of casual “happening by chance” then evolved in usage: “By chance” expanded to “unmethodical, unplanned” and (of people) “not to be depended upon.” It also took on the sense “showing a lack of interest” (think casual observer), and by the end of the 19th century, we had the sense of “informal” that is probably the most common sense today. You might think of casual as the way one acts or dresses when they don’t have to be methodical or overly thoughtful about things.

Meanwhile, back in Middle English, following the adjective-to-noun path already laid down by words like royalty, novelty, difficulty, and cruelty, the word casual gave rise to casualty, meaning “a chance encounter” — but more and more often it referred specifically to a negative encounter or a misfortune. It’s from this negative sense that casualties started to refer to military losses in a battle generally, and it makes a certain etymological sense that it traces back to a root that means “to fall.” And by 1844, casualty was used as a word to describe an individual killed or wounded in battle.

To keep the original sense alive, the word casuality “a chance happening” did get some use for a while, but it had more or less disappeared by the 1700s.

So if you think about it, casual, the more common of the two words, has strayed the furthest from its roots, while casualty stayed a bit closer. That’s just the weird, wild twistings of English language change.