When Words Get Fossilized
"There are some old words," explains Arika Okrent on Mental Floss, "that are nearly obsolete but we still recognize because they were lucky enough to get stuck in set phrases that have lasted across the centuries." Okrent lists a dozen "lucky words that survived by getting fossilized in idioms."
Here are a few examples:
You rarely see a "wend" without a "way." You can wend your way through a crowd or down a hill, but no one wends to bed or to school. However, there was a time when English speakers would wend to all kinds of places. "Wend" was just another word for "go" in Old English. The past tense of "wend" was "went" and the past tense of "go" was "gaed." People used both until the 15th century, when "go" became the preferred verb, except in the past tense where "went" hung on, leaving us with an outrageously irregular verb.
"Sleight of hand" is one tricky phrase. "Sleight" is often miswritten as "slight" and for good reason. Not only does the expression convey an image of light, nimble fingers, which fits well with the smallness implied by "slight," but an alternate expression for the concept is "legerdemain," from the French léger de main," literally, "light of hand." "Sleight" comes from a different source, a Middle English word meaning "cunning" or "trickery." It's a wily little word that lives up to its name.
"Umbrage" comes from the Old French ombrage (shade, shadow), and it was once used to talk about actual shade from the sun. It took on various figurative meanings having to do with doubt and suspicion or the giving and taking of offense. To give umbrage was to offend someone, to "throw shade." However, these days when we see the term "umbrage" at all, it is more likely to be because someone is taking, rather than giving it.
We might not know what a shrift is anymore, but we know we don't want to get a short one. "Shrift" was a word for a confession, something it seems we might want to keep short, or a penance imposed by a priest, something we would definitely want to keep short. But the phrase "short shrift" came from the practice of allowing a little time for the condemned to make a confession before being executed. So in that context, shorter was not better.
Read Okrent's complete list here.