You rack your brain but describe wrack and ruin. The origins of "rack" and "wrack" can help you remember the difference.
We have two words that sound the same: "wrack" and "rack," and people often don’t know which one to use. Do you wrack your brain or rack your brain, for example?
Rack Your Brain
Despite sounding the same, the words actually have different origins. We have racks for storing spices and drying clothes, but in the Middle Ages, the rack was an instrument for torture. This R-A-C-K spelling comes from a word that meant “to stretch.”
You stretch people on a rack (or at least the torturers did), you stretch out your clothes to dry, and I suppose if you want to stretch the metaphor, you stretch out spices on a rack so you can see all those tiny bottles at once instead of having to get a step ladder like I do to rifle through them in my cupboard.
The “mental torment” meaning of “rack” in “rack your brain” and “nerve-racking” comes from the idea of the physical torment of stretching bodies on the rack. Those are both spelled R-A-C-K.
Most of the time, you want the "rack" spelling.
Wrack and Ruin
On the other hand, the word “wrack” was originally a nautical term related to the word “wreck." In much earlier times, it meant to be shipwrecked or cast ashore. You can still use it to describe a wrecked ship, and—I did not know this—you can also use it to describe kelp and dried seaweed; I believe because of the idea that seaweed is often on the beach or “cast ashore.”
These days, “wrack” is mostly considered archaic.
Your Quick and Dirty Tip is that unless you’re using the set phrase “wrack and ruin” or talking about shipwrecks or seaweed, you almost always want the R-A-C-K spelling.
I think about death all the time, but only in a romantic, self-serving way, beginning, most often, with my tragic illness and ending with my funeral. I see my brother squatting beside my grave, so racked by guilt that he’s unable to stand. “If only I’d paid him back that twenty-five thousand dollars I borrowed,” he says. I see Hugh, drying his eyes on the sleeve of his suit jacket, then crying even harder when he remembers I bought it for him.
― David Sedaris in "When You Are Engulfed in Flames"
“Rack your brains, Ron, that should only take a couple of seconds.”
― Hermione Granger to Ron Weasley in “Harry Potter and the Deathly Hallows” by J.K. Rowling
Image courtesy of Shutterstock.
Mignon Fogarty is Grammar Girl and the founder of Quick and Dirty Tips. Check out her New York Times best-seller, “Grammar Girl’s Quick and Dirty Tips for Better Writing.”