Weegy: In the narrow sense a "curse" is an expression that calls down ill/judgment, either on someone else, or on one's self, as when taking an oath, such as, "If I am lying, [ may I be struck dead on the spot!" (The opposite sort of speech is a blessing.) So the original "curse words" would be those used to call down a solemn curse.
But in common speech we mix this together with other categories of "strong language" which one is either not supposed to speak (at least in certain settings), or to use with great care, including:
1) swearing - taking of a solemn oath (which may include or imply a curse if you break it)
2) profanity - often used to refer to 'crass language' or 'foul language', but it originally means language which dishonors, or treats lightly as "profane" [common, 'vulgar'] persons or things that should be honored as sacred. (In the first instance, this means sacred things esp. associated with God, etc., the name of God, as well as highly regarded people [such as a king].)
If you think about it you can see how all these types of language are related and how, for instance, "dirty [vulgar] words" end up being called "cursing/cussing" or "swearing". Also, note that uttering a curse in a formal oath or swearing an oath is usually considered acceptable - IF done in the right context, with due seriousness. It is tossing such things around lightly (again, treating the special as common/profane) that is the problem. ]
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