Sherry Beth Connot writes:
Every time I read how someone wracked their brain, I think it should be racked, and according to my dictionary it should. Can you explain why wracked is being used this way?
The words rack and wrack have been confused with one another for a very long time. Sometimes the expression “to go to wrack and ruin” is written as “to go to rack and ruin.”
The word rack has numerous meanings, both as a noun and as a verb. As a noun it originated from a word for “framework” which was probably related to a verb meaning “to stretch out.” The original framework was no doubt used for some innocent occupation such as stretching leather. Later on some evil so-and-so adapted that kind of rack for the purpose of torturing human beings by stretching their limbs.
It is from the torture rack that we get the expression “to rack one’s brains.”
The word wrack, with its identical pronunciation, is related to Old English wraec “misery” and wrecan “to punish.” In the fourteenth century wrack took on the meaning “wrecked ship.” In time it came to mean “seaweed” or anything cast up upon the shore. The expression “to go to wrack and ruin” means to fall into a state of decay or destruction.
The written form “wrack one’s brains” is, therefore, incorrect.
In my view, “to go from rack to ruin” is also incorrect, but the Free Dictionary offers entries from both the McGraw-Hill Dictionary of American Idioms and Phrasal Verbs and the Cambridge Idioms Dictionary which seem to find either spelling acceptable.