Swearing
Swearing originally meant making an oath, and this usage is still current in official and legal contexts in some countries. A court witness will have to swear to tell the truth, sometimes by the name of a deity or upon things considered holy.
Use of this type of swearing in inappropriate or trivial circumstances, or in some traditions "taking the Lord's name in vain," was considered wrong and sinful. The term swearing in common speech took on this meaning. Some current swearwords have this literal origin, either in straightforward use, e.g., for Christ's sake, or by way of a minced oath, e.g. cor blimey (from God blind me).
In current use, swearing is generally synonymous with using any profane language.
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