No, that's not a misspelling. Sure it sounds weird to the ear, but people who know the term's history and meaning prefer the original. "Card sharp" first appeared in the 1880s and meant a card player who tricked or scammed others. "Card shark" appeared much later, in the 1940s.
Many people assume that the mix-up simply comes from speakers who either thought "shark" sounded better or misheard the word originally. But that may not be the case. Linguists have traced the history of both "sharp" and "shark" to their original usages, and though it doesn't appear that either word derived from the other, there are a lot of similarities in meaning. "Shark" comes from a 17th-century German word schurke, which meant "someone who cheats." "Sharping" came about around the same time and meant "swindling or cheating." The words "loan shark" and "sharp practice" come from these words as well.
So technically, "card shark" could be correct. But because "card sharp" appeared first, many linguists want to preserve it. Whether they'll succeed is anyone's guess, but it's a sharp point of contention for many.
Wow! I never really thought that much about it until now. I guess I had written it off in my mind as being like "pop" and "soda," that it seemed to changed with what part of the country you lived in. I guess I've always done too much reading to do anything but automatically accept them both, but it's fascinating.
A weather term used for solar heating, particularly over a cold spot in the atmosphere triggering a lot of showers and thunderstorms.
It's a word we've heard a lot more of here in New England this summer as we've had an unusual amount of cloudy wet days.